Yup,
nothing like a Defrag,
Sorting through your computers registry for errors,
Disabling several completely useless startup applications,
Virus Scan + removal
spyware scan + removal
A good dusting,
and a replace of the thermal compounds to get your computer running like new again.

Never a bad idea! While you're at it, you might want to hunt down any old applications you don't use and perform the most important kind of maintenance of all: backup.

You guys just have to keep rubbing it in, don'tcha?

What?
Its true,
You should Make regular backups of your system,
This is were a slave hard drive comes in handy.