Big Problem!!!help please!!!

Ok. First my computer contains:

ASUS Striker II Nforce 790i Ultra Sli
Intel Core 2 Quad Q9770 3.2Ghz
4 x 1Gb OCZ SLI EDITION 4GB 1600Mhz DDR3
2 x XFX 9800GTX+ 512MB (2-way SLI)
2 x 1 Western Digital Raptor 350GB (Raid 0)
1 x Western Digital 1TB

I used water cooling for my cpu and for my motherboard chipset....

I use windows xp professional with sp3, older i was using windows xp 64bit but i change to 32bit to solve the problem ( nothing change)
My problem is, when i try to see a movie, ( with VLC player) always my pc stuck... Some times it's happens when i play games..
I've tried different version of drivers but nothing changed.. The problem still not fixed. Now I' am using 181.22 Note: i was using all versions from 178.13... I' am despaired... I don't know where is the problem, i spend a lot of money to build this computer....

I want your help please!!!!!

Thank you very much!!!!

i don't have any error message, when i was trying to see a movie it's stuck (at any time), i did not try to play from other player's i will try and i post my result's.. also i have not had problems with crysis and call of duty, all my games work's perfect exepted nfs, ( I forgot to post that), I take 45-50fps on crysis and 60-75fps on call of duty with A++ 1680*1050 high quality also my cpu temps it's 25-35* when i play game always it's 45-50* (Kel). how i can't find my GPU temp ??? also My power supply is THERMALTAKE W0133 TOUGHPOWER 1200W

ok my friend i will try GPU temp ,other player's and SLI profile... and i will post my results.
about vlc player P you can't found it here http://vlc-media-player.en.softonic.com/ it's player that can you add subtitles on your movie...

pr2thej i think that the problem is biggest, I tried to play movies ( e.c: avi,mp4,divx) with media player, media player(clasic) and also a download Vidmex but nothink, the same think in all players. Also i forget to say that some videos(1-2 movies) some times watched the movie and i don't have problems, if i saw the movie and try to play again the problem comes again..note: I have format my computer before 5 days so i don't think so that the problem it's on windows........ any other idea my friend???? I am gonc be crazy!!!!!!!!!!!