I've done all the things I can think of to fix/identify the issue:
* Looked for anything new or unusual in the startup log and the process task manager
* I did a system restore to about a week before the problem started (I don't have points that go any further back)
* Ran Adware and Spybot S&D (identified 2 or 3 minor issues, not unusual, and corrected those with no noticeable change in performance)
* Ran a virus scan (I use avast!) - no issues
* Ran scandisk
* Defragged my pagefile (had a slight positive effect on preformance)
* Ran CCleaner
* Defragged the hard drive
If I had to make a guess what the issue is I'd guess my computer is slightly overheating - which I've heard can cause the computer to start running the CPU at slower speeds, till it cools down. I ran SpeedFan and it shows lots of little flame icons on the list of detected temperatures- which I'm thinking are not good. If this could cause my computer to slow down any information on how to verify this is the problem and to fix it would be appreciated.
I'm running out of ideas on what could have/could be causing this problem so any suggestions would be appreciated. This is my only computer so I am anxious to get it fixed.
Thanks for your help!