Lag with video games

how can I tell if I'm over heating? I have Mcafee virus scanner.

Kill McAffee - use a removal too if available and switch to Microsoft Security Essentials. Then use HWInfo32 to monitor and post your temps - is this a laptop or desktop? Uninstall any system cleaners or similar performance apps.

Alright MCaffee is gone but how do I tell if I'm over heating in HWInfo32?

Actually I got how hot my computer is this is what it read in Celsius:

CPU Digital Thermal Sensor
CPU#0 Core0 Value: ~54.0-52.0 Min: 52 Max: 60
CPU#0 Core1 Value: ~51.0 Min: 50 Max: 63


nVidia MCP
MCP Tempurature Value: ~61.7 Min: 61.3 Max: 64.2


S.M.A.R.T.
Toshiba MIK3255GSX Value: 35.0 Min 35.0 Max: 35.0

This is what I had, and the numbers were switching just a little bit during then but still in the same basic tempurature

That seems OK - GPU a bit hot but otherwise fine - I'd test the hardware now - schedule chkdsk by right clicking your drive and in the tools, tick both boxes and reboot. Then run Memtest 86+ for one pass. Post back the results.

Right clicking my drive? Where do I this?

In windows explorer, right click your C: drive.

Ok I did that, how do i do the memory test thing?

Did you reboot and did your hard drive pass? Download Memtest86+ and burn it to CD - then reboot and let it run for one pass:

Memtest86.com - Memory Diagnostic

Note the disclaimer about 4GB of RAM.

I don't know if I passed, it finished the disk checking, took about 3 hours to do and now I hope it doesn't do that everytime I start up the computer. It's a lap top by the way. I'm downloading now