*Do you do your computer housework on a regular basis?
If you do everything should be ok.
Eg
Check Disk.
Defragment
Disk Clean Up
Error Checking
Temporary Files Removal
* IE.8 - Safety - Delete Browsing History. -
*Make sure your windows Update is running.
*Have you checked in Task Manager/ Processes/ All Users to see what is running there?
*Do you check in Event Viewer for errors frequently?
Note any with a red mark in Application & System.