Ok the reason why WinXP uses more resources is becasue it's intended to be used on more powerful rigs. Like 2+ ghz CPUs, hi-speed 100gig HDDs, and 512megs of RAM. *NOT* a system made 6/8 years ago that was BARELY running 300mhz and 128megs of Ram, and two gig hard drives with UDMA.
So why should microsoft not take advantage of new hardware that comes out? They MUST update thier software to keep up with new hardware advances, and also take advantage of how RAM is getting cheaper all the time, with everyone running a GIG of RAM if not more.
Also if we were ALL using win95 (for example) after 9 years, we would have PILES of CDs with software and drivers to support all the new hardware we have now for it to work with 95. Imagine how long it would take to install all that crap?
What if we were still using Win 3.1? we would have probably have upteen consecutive service packs that we would have to install one after another, and loads drivers and software installs to get it to work right with the hardware we use today.