I do fine with a an upgrade I did a 3 years ago to put my laptop at 512Mb RAM. That should be good enough for XP.
I'd however replace avast with AVG.
Just so you can compare with your own system, I have a Toshiba Satellite Pro SP6000, 512Mb RAM, 20Gb hard drive and a PIII-M at 1GHz. I run Visual Studio 2005 Professional on it without complaining much about speed. I just close services I don't need and avoid falling prey to the useless... like themes, background screens and such. In fact I prefer a lot more windows 2000 interface than that of XP so I run in classic mode.
