I've not tried all those options (but about a million others not on that list

) so I'll give the remaining ones a try to see what happens.
4. Win7 (have tried a reinstall of this)
5. 4870x2 (tried 9.7-9.11 cats)
6. 4GB of
underclocked ram. Will try playing with this more.
7. Game files verified and even deleted+redownloaded. Same with Steam itself.
I've also tried playing with file permissions and -windowed and -sw...zero luck so far.
The irritating thing is that it used to work for the most part but crash a level or two in...now it exits the moment the intro video finishes.
Thanks for the suggestions - I'll try them and post my results here