You have anti virus software downloaded and it may not be the case, though some virus is not dictated. There are many reasons computers are slow. Are you using cable or dial up to get into internet? Corrupted or conflicted program files makes the computer run slowly. If you have cable then the bit it is receiving and forwarding is not optimal you can not get the desired result. You can check with cable provider if this is the case with you. Always save important file in floppy or USB disk, incase you have to reformat and see if it works will be plus point. You can reformat again and see if it works? Dude, do not download any thing that is not secure and emails that is not known to you. It may be helpful but not a solid answer. Hoe experts will share their views.