I've seen a sweet deal on a Dell laptop but it only comes with Vista, anyone tried formatting a Vista comp and installing XP and are there any issues or problems that may crop up?

Did you try asking them not to install Vista? Just get an empty machine and install XP yourself. Should be no problem getting the disk from Dell if you don't already have it. I know when I bought my latest Dell in October I had to argue with them not to install any junk on it. They were more than willing to send me an empty machine and the XP disk to install windows myself. I figured for the money I was paying I shouldn't have to do that and finally got what I wanted but the point is they were very willing to send me the machine with nothing in it so I would think they would do the same for you.