What settings have you tried running the game?  Don't crank them up too high.  I had a 7950GT once, latest games had to be run all medium for smoothness, and at the time the Forceware 169.xx drivers worked for me but I still had XP.  You would have to find some of the earilest with Win 7 support.  Go to nVidia's site and look up archived drivers.   Looks like the earliest certifed for 7-series and Win7 would be in the Forceware 190 range.  Google info on these drivers, read up success stories or even complaints from peopel who post questions or comments, find out what they expected from which games, etc.
 
Keep in mind Windows Vista and 7 are resource hogs and can take almost 1GB for themselves compared to XP averaging below 300MB.  Since you only have one 1GB of RAM installed, your games may be shallow breathing.  Try getting another 1GB at the very least, or maybe exchange for two 2GB sticks (though with 32-bit the max you could use is 3.5GB which is more than enough).  
 
The drivers upgrades are free, but you may have to buy more RAM.

Hey man you aren't the only one. I'm running 2 7600GT SLI cards in my older AMD system. I downloaded a pre-version of Windows 7 awhile ago and I've been too lazy to update it. So it's kind of a Windows XP/7 version but not really. I'm good with most games cause I use the SLI config to boost the system and I have 2gb of RAM which helps. I am seeing a lot of problems with Call of Duty Black Opts so I'm looking to upgrade soon. Sounds like you are in the same boat... I'm new to the forum as well, but I've already learned so much. Good luck. 

can any1 help me with this situation ive got, all i wana be able too do for now is play cs 1.6 without any fps drops i mean suely a dual core processor and a 256 bit graphics card should run very smooth but is isnt please could any1 give me some sort of advise on wear ive gone wrong or what i need to do for my fps to become stable..please this is doing my head in..? many thanks michael

cheers for the help cactuspwr.. my ram usage jumps about from when i boot up in the morning until i go to sleep and plus ive done a little tweakin ... its saids at the moment that im using 521mb but ive seen it at 400  the most ive ever seen it at is 600.. i know i need more ram and ive got some on the way... my biggest problem is weather the 7900gt can handle windows 7 and whats the best compatible driver to use..? i mean surly i should be able too play cs 1.6 with no problem... im seriouly thinking of down grading to xp... but really dont wana go thew all that hassle just too get a stable fps.... oh and by the way i switched from an 22 inch W/S lg screen and the res was 1440-900 to a 19 inch screen with a res of 1280-1024 like you said and i have noticed abit of an inprovement... but still having trouble with the drivers... Any1 in a simalar situation that could gives a clue on what too do..? many thanks michael