please paste the output of:
gconftool --get /apps/f-spot/ui/main_window_width

and also the output of 
f-spot --debug

thanks.

icarii@icarii-kubuntu:~$ gconftool --get /apps/f-spot/ui/main_window_width
No value set for `/apps/f-spot/ui/main_window_width'                      
icarii@icarii-kubuntu:~$ f-spot --debug                                   
** Running f-spot in Debug Mode **                                        
** Running Mono with --debug   **
[Info  23:11:38.131] Initializing DBus
[Debug 23:11:38.790] DBusInitialization took 0.541168s
[Info  23:11:38.791] Initializing Mono.Addins
[Debug 23:11:39.980] Mono.Addins Initialization took 1.189024s
[Info  23:11:40.018] Starting new FSpot server
[Debug 23:11:41.530] Db Initialization took 0.384259s
Domain: 'Gtk' Level: Critical
Message: gtk_window_resize: assertion `width > 0' failed
Trace follows:
   at GLib.Log.PrintTraceLogFunction(System.String domain, LogLevelFlags level,System.String message)
   at GLib.Log.PrintTraceLogFunction(IntPtr , LogLevelFlags , IntPtr )
   at Gtk.Window.gtk_window_resize(IntPtr , Int32 , Int32 )
   at Gtk.Window.gtk_window_resize(IntPtr , Int32 , Int32 )
   at Gtk.Window.Resize(Int32 width, Int32 height)
   at MainWindow.LoadPreference(System.String key)
   at MainWindow..ctor(.Db db)
   at FSpot.Core.get_MainWindow()
   at FSpot.Core.Organize()
   at FSpot.Driver.Main(System.String[] args)
[Debug 23:11:43.347] QueryToTemp took 0.022209s : SELECT id, time, uri, description, roll_id, default_version_id, rating, md5_sum FROM photos  WHERE id NOT IN (SELECT photo_id FROM photo_tags WHERE tag_id = 2) ORDER BY  time DESC
[Debug 23:11:43.629] PhotosPerMonth took 0.004016s
[Debug 23:11:43.636] TimeAdaptor REAL Reload took 0.221658s
The program 'f-spot' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadRequest (invalid request code or no such operation)'.
  (Details: serial 419 error_code 1 request_code 143 minor_code 19)
  (Note to programmers: normally, X errors are reported asynchronously;
   that is, you will receive the error a while after causing it.
   To debug your program, run it with the --sync command line
   option to change this behavior. You can then get a meaningful
   backtrace from your debugger if you break on the gdk_x_error() function.)
icarii@icarii-kubuntu:~$

set that setting to something like 400 (using gconf-editor). Please report if it works or not.

in any case, do not close the bug.

in any case, this Gtk-Critical shouldn't make the probram stop, unless you're running a gtk version compiled to raise errors on critical warnings (or have a flag set do to it a runtime.)

where did you got your gtk from ? version ?

Not sure how to set that setting.

Unless one of the package I installed changed it, it the one that installs with Kubuntu 8.10. How do I check?

thanks for the help.

launch gconf-editor
navigate on the left to apps/f-spot/ui
on the right you should find

main_window_width
main_window_height

set them to something, like 100. if they don't exist create them, as integer.

(p.s. when you answer unset the NEEDINFO flag on the bug)

if it's the gtk coming from ubuntu, report the bug to launchpad

I am running Kubunut 8.10 with KDE 4.1. It does not have gconf-editor and will not let me install it. I went to start-system setting-windows behavior,windows-specific and create an entry for f-spot and made the initial windows size 100x100 but that did not work. I still get the same error.

Will f-spot run under kubuntu 8.10 KDE4.1?

you can set the keys using gconftool --set.

gconftool -t int --set /apps/f-spot/ui/main_window_width 100

f-spot run fine on kde, provided that yo uinstalled the right dependencies. if kubuntu provides f-spot but f-spot doesn't work, it's a building issue.

so, please try to set the key and restart f-spot. chances are high that it'll crash a bit further, but it'll help me to be sure of what's going wrong (debug version of gtk, or compiled to crash on warnings)

Ok, i made the change and this is what I get.

icarii@icarii-kubuntu:~$ f-spot --debug
** Running f-spot in Debug Mode **
** Running Mono with --debug   **
[Info  22:07:38.537] Initializing DBus
[Debug 22:07:38.946] DBusInitialization took 0.301211s
[Info  22:07:38.946] Initializing Mono.Addins
[Debug 22:07:39.294] Mono.Addins Initialization took 0.347641s
[Info  22:07:39.305] Starting new FSpot server
[Debug 22:07:40.196] Db Initialization took 0.1032s
[Debug 22:07:40.804] QueryToTemp took 0.101074s : SELECT id, time, uri, description, roll_id, default_version_id, rating, md5_sum FROM photos  WHERE id NOT IN (SELECT photo_id FROM photo_tags WHERE tag_id = 2) ORDER BY  time DESC
The program 'f-spot' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadRequest (invalid request code or no such operation)'.
  (Details: serial 419 error_code 1 request_code 143 minor_code 19)
  (Note to programmers: normally, X errors are reported asynchronously;
   that is, you will receive the error a while after causing it.
   To debug your program, run it with the --sync command line
   option to change this behavior. You can then get a meaningful
   backtrace from your debugger if you break on the gdk_x_error() function.)
[Debug 22:07:41.059] PhotosPerMonth took 0.015185s
icarii@icarii-kubuntu:~$ gconftool --get /apps/f-spot/ui/main_window_width
100
icarii@icarii-kubuntu:~$

I don't know if this help but I ran f-spot with a backtrace. The output doesn't help me, but it might help you.

icarii@icarii-kubuntu:~$ mono --debug /usr/lib/f-spot/f-spot.exe                
[Info  22:27:42.739] Initializing DBus                                          
[Info  22:27:43.279] Initializing Mono.Addins
[Info  22:27:43.681] Starting new FSpot server
The program 'f-spot' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadRequest (invalid request code or no such operation)'.
  (Details: serial 419 error_code 1 request_code 143 minor_code 19)
  (Note to programmers: normally, X errors are reported asynchronously;
   that is, you will receive the error a while after causing it.
   To debug your program, run it with the --sync command line
   option to change this behavior. You can then get a meaningful
   backtrace from your debugger if you break on the gdk_x_error() function.)
**
ERROR:../../mono/io-layer/handles-private.h:160:_wapi_handle_set_signal_state: assertion failed: (thr_ret == 0)
Stacktrace:

  at (wrapper managed-to-native) System.Threading.NativeEventCalls.SetEvent_internal (intptr) <0x00045>
  at (wrapper managed-to-native) System.Threading.NativeEventCalls.SetEvent_internal (intptr) <0xffffffff>
  at System.Threading.EventWaitHandle.Set () <0x00026>
  at (wrapper remoting-invoke-with-check) System.Threading.EventWaitHandle.Set () <0xffffffff>
  at Banshee.Database.QueuedSqliteDatabase.QueueCommand (Banshee.Database.QueuedSqliteCommand) <0x000a1>
  at Banshee.Database.QueuedSqliteDatabase.ExecuteNonQuery (Banshee.Database.DbCommand) <0x00043>
  at Banshee.Database.QueuedSqliteDatabase.ExecuteNonQuery (object) <0x00046>
  at PhotoStore.PhotosPerMonth (FSpot.Query.IQueryCondition[]) <0x000e4>
  at FSpot.TimeAdaptor.DoReload () <0x00088>
  at (wrapper runtime-invoke) System.Object.runtime_invoke_void (object,intptr,intptr,intptr) <0xffffffff>

Native stacktrace:

icarii@icarii-kubuntu:~$

I have linked bug 297406 in Launchpad to this bug.
https://bugs.edge.launchpad.net/f-spot/+bug/297406

Not able to reproduce on a 32-bit system or my 64-bit (vmware) system.
I did get the gtk error but F-spot did not crash.
After changing the main_window_width and main_window_height the gtk error is gone.

*** Bug 561852 has been marked as a duplicate of this bug. ***

Please see:
https://bugs.launchpad.net/ubuntu/+source/f-spot/+bug/297406/comments/17
https://bugs.launchpad.net/ubuntu/+source/f-spot/+bug/297406/comments/18

On my machine, I run F-Spot 0.5.0.3 on Ubuntu 8.10 (AMD64)
f-spot crash with the error mentioned above if I use radeon or radeonhd drivers. Using the proprietary fglrx driver does not make the crash happen! 

I am seeing this bug on f-spot 0.5.0.3 on Ubuntu 8.10. System is 2.6.24-21-rt on AMD Athlon(tm) 64 Processor 3000+ with i686 architecture. 

I also have the bug with the latest SVN snapshot, and I managed to localise it to a call to Core.Organize (called around line 291 of main.cs), which in turns calls MainWindow.Window.Present(). Window here is a Gtk.Window, so I suspect that the bug is being triggered in one of f-spot dependent libraries? Will debug further when I have time.

BTW. with regards to antoine's bug report above, I am using fglrx drivers version 8.543.

Here's f-spot's dependencies list with some versions:

f-spot
  Depends: libart-2.0-2
  Depends: libatk1.0-0
  Depends: libc6
  Depends: libcairo2
  Depends: libexif12
  Depends: libglib2.0-0
  Depends: libgnomeui-0
  Depends: libgnomevfs2-0
  Depends: libgtk2.0-0
  Depends: libjpeg62
  Depends: liblcms1
  Depends: libx11-6
  Depends: mono-runtime
 |Depends: libc6
 |Depends: <libc6.1>
  Depends: <libc0.1>
  Depends: libflickrnet2.1.5-cil
  Depends: libgconf2.0-cil
 |Depends: libgl1-mesa-glx
  Depends: <libgl1>
    libgl1-mesa-glx
    libgl1-mesa-swx11
  Depends: libglade2.0-cil
  Depends: libglib2.0-cil
  Depends: libglitz-glx1
  Depends: libglitz1
 |Depends: libglu1-mesa
  Depends: <libglu1>
    libglu1-mesa
  Depends: libgnome-keyring1.0-cil
  Depends: libgnome-vfs2.0-cil
  Depends: libgnome2.0-cil
  Depends: libgphoto2-2
  Depends: libgphoto2-port0
  Depends: libgtk2.0-cil
  Depends: libmono-cairo2.0-cil
  Depends: libmono-corlib1.0-cil
  Depends: libmono-corlib2.0-cil
  Depends: libmono-sharpzip2.84-cil
  Depends: libmono-sqlite2.0-cil
  Depends: libmono-system-data2.0-cil
  Depends: libmono-system-web2.0-cil
  Depends: libmono-system1.0-cil
  Depends: libmono-system2.0-cil
  Depends: libmono2.0-cil
  Depends: libndesk-dbus-glib1.0-cil
  Depends: libndesk-dbus1.0-cil
  Depends: libxcomposite1
  Depends: dbus
  Depends: gvfs-bin

Seems to be a driver problem, am going to close this here, should be in the distribution.