A little more information would sure help.. Operating system, age of the machine, EXACT model number, etc.. Which antivirus and antispyware tools did you use? The more information you give us, the better informed our answer will be.
In the meantime, if Windows XP, have you tried using System Restore? Click on Start-All Programs-Accessories-System Tools-System Restore.. When the SR window loads, select "Restore my computer to an earlier time".. At the next "Calendar" screen, click on a bold date which is previous to your problems.. Click on "Next" and follow the prompts to restart the computer and restore back to when things were good.
Hope this helps.
My laptop freezes after only a few minutes of being on the internet, Also when typing the letters are slow to appear. I have scanned for viruses and ad ware. It also will not completely log off when I try to turn it off. This problem just started a few days ago.