[Help] Slow Computer

Backing up your entire system now won't help... The backup will still have the problems. When doing a clean re-install, all files, data files ect. are backed up... What is your decision? Do you want to go ahead and do a re-install?

No, I mean install a fresh copy of Windows 7 from a retail copy.

...Do you mean a complete image of the current state of your computer? If you can't figure it out now... Even with the help of us... I doubt you would be able to find out the problem.

See if flushing the DNS cache helps a bit ....

Right click on a command prompt and choose to run as Administrator.
Copy/paste ipconfig /flushdns press 'enter'

Next, download TFC by Old Timer TFC - Temp File Cleaner by OldTimer - Geeks to Go Forums and save it to your desktop.
Save any unsaved work. TFC will close ALL open programs including your browser!
Double-click on TFC.exe to run it. If you are using Vista/Windows 7 right-click on the file and choose Run As Administrator.
Click the Start button to begin the cleaning process and let it run uninterrupted to completion.
Important! If TFC prompts you to reboot, please do so immediately. If not prompted, manually reboot the machine anyway to ensure a complete clean.

TFC (Temp File Cleaner) will clear out all temp folders for all user accounts (temp, IE temp, java, FF, Opera, Chrome, Safari), including Administrator, All Users, LocalService, NetworkService, and any other accounts in the user folder. It also cleans out the %systemroot%\temp folder and checks for .tmp files in the %systemdrive% root folder, %systemroot%, and the system32 folder (both 32bit and 64bit on 64bit OSs). It shows the amount removed for each location found (in bytes) and the total removed (in MB). Before running, it will stop Explorer and all other running apps. When finished, if a reboot is required the user must reboot to finish clearing any in-use temp files.

Yes, svchost.exe are Services. All of them.