What happens with system restore?

I have a multi atacking virus. w32 alcra.b

I have done spyware, adware, and virus for 3 days and it still is attacking. I was thinking about system restore cause it seems to be attacking anything mircosoft, but I don't have a product number or an intallation cd for xp. I bought my computer at bestbuy. What should I do.

What happens with system restore?antivirus

System Restore doesn't need product key. It will restore your computer to an earlier date. All the programs that got installed previously and the state of the registry that time will be back to that date.

For more details

http://en.wikipedia.org/wiki/System_Rest...

When did this problem start happening?

If only this week try performing System Restore. Restore your computer to an earlier date

To do System Restore:

a. Click on Start

b. Click on All Programs

c. Click on Accessories

d. Click on System Tools

e. Click on System Restore

f. System Restore will open

g. Click on Restore your computer to an earlier time

h. Click on Next

i. Try to choose a date last week or days ago that you are not having this problem.

g. Just follow the prompts, Click on Next

NOTE: The computer will logoff just let the computer do the restore

Try optimizing Internet Exlorer Browser

a. Check first the version