I found that we have lots of data,Software and installed programs on our PC's. Our internet use of every time make lots of temporary data in our Hard Drive's and capture HD's sectors and system resources who makes system slow and slow day by day.
By doing these things we can free up our system resources to work on maximum performance.
Free Up Disk Space
Speed Up Access to Data
Detect and Repair Disk Errors
Protect Your Computer Against Spyware
LinkI trying these things from past but i found these written tips in Microsoft so i thought i should share with you all.
I hope you will find it usfull too.