This restore feature wipes the drive completely, and installs Vista just like it was when you first got it.

 

Save any data you need before using this utility.

Before you do this, you might want to consider WHY it's running slow.  You have a larger disk drive, so it's unlikely that it's full yet.  But Spyware is notorious for slowing a system down.   When my daugher-inlaw's new Dell slowed to a crawl, I ran a spyware remover  ( Lavasoft, available as freeware) and found 700 pieces of spyware.  They were all RUNNING in conjunction with Windows.  When they were cleaned off, the system normalized.

 

My point is:  if you do a restore, take some steps to make sure you won't have to do it again.

 

chuck r.