1. You have to know the version of the OS that you intend to install. XP for example limited us to 127GB in many cases. The question would be "What version of XP was supplied with the machine?"

2. Hard disks for this model is IDE or SATA. Yes you will hear a dozen other names but these are the two types. Your machine takes the ubiquitous 2.5 inch laptop drive you find at newegg.com, geeks.com, etc.

3. OH, you want to avoid reinstalling the OS? Clone the drive. I used this cable and G4U. Some look up EASEUS. (no link for that, you do the search.) Cable example at http://www.geeks.com/details.asp?invtid=2020&cat=CBL

Example IDE hard disk at http://www.geeks.com/details.asp?invtid=HM160HC-N&cat=HDD

I'd stick to 5400 RPM.
Bob

PS. If you ask me if this will work, I must not answer. It means you didn't do the research.