As it is WinVFX that crashed
a) It is an external library, that handles all the GFX. So I cannot debug or change it any. (I do have the source, but the main code is in Microsoft assembler, and the version of MASM is old, and seems no longer obtainable).
b) If it is WinVFX that is dying, that points to something to do with DirectX, or your video card etc. Possibly video RAM left locked by a previous game?
One point to mention with DirectX, is that it is often not a good idea to play game A, then attempt play game B in the same session without first rebooting your PC.
This is especialy true with any game that crashed - which I find a common occurence with Civilisation IV (or whatever the latest version is), it is crash city with ATI based cards it seems!
. Even with a 128MB card, it crashes with a complaint about "insufficient video RAM". When it does so, it seems to have left all the video memory on the card locked, and so other games (or anything else wanting to use accelerated graphics) complain. Any save game will then load and usually play OK after a reboot of the PC, so I suspect a leak where parts of the VRAM (or off screen RAM used for video work ?) are being left locked, as this one appears towards the end of long sessions of play usually.
I also find that it is best to reboot the PC after a session of Sims2 as well, crash or no crash, if wanting to play another game.
Just as a matter of interest - had you done any graphics card intensive stuff or directX or video media (e.g. playing video will use DirectX or Directshow/play with e.g windows media Player thingy) in the same session (since reboot) before loading up that game that crashed?.
Any media players active in the background (Including say a streaming video web page)?. It is not the best of ideas to try any sort of directX game with a media player session (or web page with streaming stuff) in the background. They may well reserve VRAM even if "idle". So both applications will be "fighting" for the same resources most likely!. (and a streaming webpage will probably not be idle, even if minimised to the task bar). Possibly includes RSS feeds and so on.
Cheers
Andy