Daily
Run a virus(AVG Free,
http://free.grisoft.com/doc/2/lng/us/tpl/v5 and spyware scan(Ad-Aware SE Personal,
http://www.pcworld.com/downloads/fil...id,7423,00.asp.
Weekly
Backup your hard drive (or at the least your files).
Defragment your hard drive.
Update your spyware and anti-virus definitions(Ad-Aware SE updates,
http://www.lavasoftusa.com/support/download/)
Monthly
Run disk cleanup
Empty your recycle bin
Empty your temporary files
Empty prefetch folder
Occasionaly
Uninstall unused or unneded programs
Use RegClean to clean the cobwebs out of your registry (
http://www.pcworld.com/downloads/fil...id,4666,00.asp)
Remove unncessary startup items using msconfig
If anyone can come up with some other stuff to add just let me know.
There's some links.