Like having obsolete hardware not fit to run Vista? Protip; this thread is about someone with a machine that comes with Vista; wanting to ruin it with XP.
Inconsequential to the point at hand. And yes, Vista uses more memory - get this, right, Windows XP? It uses more memory than Windows Me! Golly gosh, a more recent OS that takes advantage of changing hardware standards? What an idea.
Really. Tell me about all the DX10 rendering you do in games? Seems like a pretty serious software deficiency right there. And how is it installing SATA drivers from floppy drive at boot time? And being able to burn to DVDR's without additional software? Add to that the fact that any malware runs as administrator immediately under XP without user intervention and it's easy to see which is the less compatible and stable OS.
"For quite some time" meaning "Until July 2010", btw. And even then, we're in the "extended support" era meaning no updates or functionality; just hotfixes.