FPS drops to 1 every 3minutes.

What are all of the hardware components in your system? Are you talking about online play or doing single player modes where you aren't connected to the net? List your components and someone can lend a hand.

For partitioning I like to keep my OS to it's own smaller partition and try to keep any important files off it. I am not a RAID person so I go this way instead. I would never recommend doing one volume but if you have no choice...screw it.

Sometimes wiping out your OS and re-installing it can really come in handy, just like what you are considering though. Sometimes viruses hit or you screw up your registry with driversweeper ...I have even had Windows randomly end up with corrupted files and need a clean install. In any case, it is nice to have the OS separated from your other files so you don't lose anything if you have to format.

BUMP!!!!

I'm having the same problem, when I play both Wolf:ET (Online game) and Half Life 2 (Offline Single Player) every few minutes my game grinds to 1 and then 0 fps and then restabilises after about 6-7 seconds!

Manufacturer:
Hewlett-Packard
Processor:
Intel(R) Core(TM)2 Duo CPU T7300 @ 2.00GHz (2 CPUs), ~2.0GHz
Memory:
2046MB RAM
Hard Drive:
400GB (2 HDD's)
Video Card:
NVIDIA GeForce 8600M GS
Monitor:
17" Widescreen
Sound Card:
Speakers (Realtek High Definition Audio)
Speakers/Headphones:
Logitech Headset
Mouse:
Logitech MX518
Mouse Surface:
Everglide Titan
Operating System:
Windows Vista™ Home Premium

Yeh, I was thinking so. I'm usually very careful in terms of infecting my system but I suppose there is the chance.

Quite infuriating when it happens in game and I get killed :x

I've tried many virus scanners but don't have a preferred one, any recommendations?