I have problems when i start some games.
I basically CAN'T play the following games i own

warcraft 3
the elder scrolls 3(morrowind) + all expansions(goty edition)
unreal tournament 2003
unreal tournament goty edition
grand theft auto 3
runescape HD(not low detail)
pirate hunter
rising kingdoms
age of empires 3
and counting .....

i CAN play these games

diablo 2 + expansion
age of empires 2 + expansions(collector's edition)
empire earth
risk 2
and that's it....

thing is when i run the games i cannot play.. the game crashes at some point of play ( usually like 1-10 minutes)

my system requirements are good enough for the games.. and the games run PERFECTLY as long as i play till the crash..

here is my system info

video card : ATI Radeon x700 Pro
sound card : ugh didn't find this but i believe it supports 3d sound or something..
microsoft windows xp pro v2000
service pack 2
computer: Intel(R)
Pentium(R) 4 CPU 2.60GHz 2.59GHz, 1.00 GB of RAM
my computer memory is 149 Gigabytes

i think i entered everything correctly

what have i done so far?

well i have tried running the games at lowest requirements possible
i have turned off sound completely and with low/med/high requirements
i have closed all programs i can and then run the game with every setting possible(okay not every but as much as i could change and vary them)
i have searched over internet if ati radeon x700 pro is a good enough video card.. i found out : yes
i searched if somebody else had problems like this, i found out one guy basically did and there he was answered that he would have to buy a new cooler and put some paste on it. Also to try every settings and stuff .. my dad suggested me to do a format and that would delete everything in my comp and maybe then it would run.. i don't know about that... i wouldn't want to do that.

i apologise for my very faulty english, but my mother language isn't english so..

i would be grateful if you'd actually know what else could i do :P and maybe give me a little guide since i'm really bad at such deep computer stuff.

edit: did i mention that my games do not crash to desktop.. but my COMPUTER goes black and eh screen shuts down and music goes away..nothing i can do.. but computer is working..what's the deal with that..

You show that you have sp2...do you have your updates set to automatic? Have you previously been able to play these games with no issues? The reason I ask about your automatic updates is that sometimes with sp3 or 4, you might experience issues with some of these games, if your gaming software is not updated as well...just something to check into, not sure if that is your fix but it is worth a look! Good luck to you.

Also, recheck the amount of RAM your computer has. Also realize that your processor is quite dated, and you may not be getting the performance you are wanting with your pentium 4.

yes my updates are set to automatic.. and thing about my comp is.. the games run perfectly but then computer just goes black.
i don't understand what has automatic updates to do with this, and no idea what are service packs :D

that sometimes with sp3 or 4

wtf he has XP. There is no sp4 for xp?

I think your problem is overheating or not enough power. Also try the most recent ATI Catalyst drivers