2-ton wrote:
I don't have firefox or chrome on my computer...it's an old computer and I just never bothered to add them. I am not sure my disk cleanup is working right, the progress bar only goes up to two green marks, never seems to go further. Besides, it's not like my hard drive is at all full, there is plenty of space left on it. The computer just runs seems to run slower and slower. The tower also emits a bit of noise, sometimes it sounds like it is speeding up, sometimes it sounds like it is slowing down. It's not loud, but I can hear it humming.
Sounds like mine ... lol
Right now it needs a good fan cleaning.

I take it outside (the hard drive) and blow it out with an air compressor every year.It gets real dusty in my area due to the clay that abounds everywhere. =)
About your Disc Cleaner:
It takes a while to run if you haven't ran it in a while.(just like defrag)
Run defrag first start/program files/accessories/system tools/defrag...count on doing it at night when your asleep...leave it running.
Then try this - click one area at a time to clean when that dialog pops up tick just one square.
See if that speeds it up a bit.
After that do it about every 2-3 months or so.defrag and clean disk.
Just running defrag speeds you up nicely a lot of times its all you need.
Hope that helps. =)