Computer crashes when I play games?

Mine used to do that to because the baterry was loose

So you assume it isn't overheating based on you cleaning it? Bad idea. It could have old and dry thermal compound/paste. The stock cooler could be failing. Those are only a couple possible issues. Use http://www.cpuid.com/softwares/hwmonitor.html (not pro) to avoid assuming. Coretemp is another real time monitor that also records min and max temps over the course of a session. You can alt+tab out of a gaming session to check temps. Using dual monitors to see real time info is better.

Go to start and type event viewer. See what errors have been recorded.

Best guess? Your laptop is old and weak.

There's either issues with how much you have used on your hard drive, and since your trying to write new data, is it getting corrupt. Or the folder is massive and keeps getting corrupt. Virus's won't specifically crash games and no other program. Virus's mostly screw up your computer. Like they make it slow. Download programs. Have a history of what keys you click. Etc