I dunno if this helps any or not but I'm running Vista Ultimate 32-bit SP1 and "core.txt" in "C:\Program Files\Rockstar Games\GTA San Andreas\MTA" says something that may be useful:
** -- Unhandled exception -- **
Mod name = TODO
Time = Sun May 18 14:26:17 2008
Code = 0xC0000005
Offset = 0x04878C0F
EAX=04878C0F EBX=7FFD6000 ECX=021B07C8 EDX=018E793C ESI=00000007
EDI=018E692C EBP=0177FEE4 ESP=0177FECC EIP=04878C0F FLG=00010202
CS=001B DS=0023 SS=0023 ES=0023 FS=003B GS=0000
** -- End of unhandled exception -- **
BTW when I start the race it just shows the splash screen and goes back to desktop... I'm assuming this "core.log" would be the error log?