System Mechanic.

I'd advise you to check www.greyknight17.com and visit the anti-spyware-section there if you haven't allready done so. Spyware is more than 80% chance the reason your PC is slowing up... You can also post in the spyware section on this site then someone will help you through the steps if you are unsure. You came to the right place!

hmmm, I dunno man, it says I only have 19% memory left, the computer is now 2 years old.

If you mean that when you right-click your disk and click "properties" you have 20% left on your disk:

Windows needs +- 700Mb free disk space to run. If you have that much space on your disk i don't think a full disk is your problem.

I really advise you to visit the site and pursue with the steps presented. This always resolves these kinds of problems for me and i have done this a lot for my friends and on my job. If it doesnt solve it it won't do any harm and people will help you faster here when you are sure it is not spyware causing your problem. It takes a little effort ...