I have been running Windows XP now for the last 3 months on my MBP 2.16 with 2GB RAM. There has not been an application or a game that I have not been able to use. It is really weard watching winXP on my Mac.
Installation of XP under bootcamp is very similar as it is on your Sony. The only extra step is for you to run Bootcam from Your Mac and decide how big of a partition you would like your Mac to have and Your XP to have, it will prompt you to insert a blank CD and proceed to burn all the drivers you'll need. Put the WinXP CD inot your CD ROM drive and reboot with the the C key Down, and from that point forward, you won't know the difference between your Mac or your Sony (of course the Mac's Aluminum looks beats anything out there) good luck.
P.S. Parallels runs WinXP find as well, however, you will not get full speed because it only uses 1 core, and there are parts of it still emuated because of hardware. Bootcamp runs at full speed ahead.