I just want to insert something here.
If you bought a laptop, and it _did_ come with reinstallation cd's, then I would recommend installing that over your _ligit_ copy of windows.
Reason: Native hardware support. aka Drivers.
You can ignore my advice if you can find the right drivers your self.
Unless you just upgrade. imo, if your hp computer doesn't come with proprietary hardware, reinstall that shit. same goes with sony and any other computer that comes preinstalled with spyware.
edit-I found a tablet pc edition release floating around the interwebs. hint: ETH0
just get winxp pro and download all the drivers from the manufacturer's website. xp pro is the way to go right now. vista is too new and you'll probably just have problems if you actually use your computer/laptop to do stuff other than say, word processing or surfing the series of tubes (internets). i was going to upgrade to vista, but then i read about the incompatibilities and security issues it has right now and decided to wait.
you can find xp pro floating around the interwebs too. hint: ?