I am afraid I have never used WAMP on a XP Home machine - all my PC's are XP Pro or XP Media Center. However, I am almost sure that WAMP works on XP Home.

I have never tried to install Apache/PHP/MySQL from scratch as I just run XAMMP or WAMP and then I am up and running in 5min.

If you are low on space then you can A) install XAMMP to a USB drive (I am using mine right now) or B) get a copy of a bootable Linux like Ubuntu or Knoppix and run your server off the CD.

But if WAMP is too big you can use XAMMP Lite as it is only 140MB in size.