It could be a virus. It could be hardware getting bad.
You will need a computer working for at least some time to do a good scan. Try a BOOTABLE ANTIVIRUS CD (google that). If that freezes also during execution, you'll know it's a hardware issue. If it completes, but doesn't locate the problem, first do a system restore back to before 'recently', then - if necessary - a system recovery back to factory conditions using the tools that came with your computer. With no hardware issue and the software back to as it started all should be fine.
Note that the system recovery will delete all your files. You might want to copy everything to a (better: two) external hard disks or USB-sticks first. In that case, do it after booting from some Unix live CD/DVD or (after getting your hard disk out) on another PC.
<span class="Apple-tab-span" style="white-space:pre"> So i use my computer to write and to surf the net. Recently i noticed that my computer was starting to lag a bit. Then all of a sudden it started freezing and i had to hard shut down my laptop. Ever since then i can only be on my laptop for about 2-5 min before it freezes and i can not do anything. I definitely think it is a virus. How to i clean my laptop of this virus so i can actually use my laptop. It is very stressful trying to work and not being able to doing anything. I tried a one time pc fix and it made my computer a bit faster but after a few min it still freezes and i have to shut it down. I use AVG anti-virus and ad-aware. However i have not been able to run them since my computer freezes so much. Someone please help........