Absolutely the best software I've found thus far for Windows 7 management and optimization. You have to pay for the software, but you can download a Trial, run the Optimization wizard once and that should make some lasting changes to your computer. From there you can uninstall and then just use CCleaner
as a maintenance program for registry maintenance and temp file cleanup.
If that doesn't make a difference, you need to reinstall your OS, then make a baseline image of the OS and installed programs/favorites/etc. I suggest using Clonezilla and the local drive for ripping/restoring an image to/from your PC. You'll need a drive besides the root C: to store the image. May I suggest making an additional partition from your root drive to house needed data, etc?
's a guide on doing just that.
Humans are the only creatures that won't live up to the their potential. Give everything your all. When you die, die on E.
So I ask you, what do you intend to do now?