erm, isn't the reason it has less memory usage and CPU demand because it was designed for lower quality hardware? and you yourself said you can just turn off UAC
my point is this: you saying that XP is better than 7 is like saying N64 is better than Wii, or iPhone 2 better than iPhone 4S. People may have preferences, because they're used to using a certain OS, but facts are facts, 7 is an UPgrade from XP because 7 was designed for better hardware.
Companies and businesses that use XP, as you mentioned, probably only use XP because they have crappy hardware :P
keyword: smaller computer shops
As for the less restrictiveness, if your looking for non-restrictive, just use linux! :P
I'm not hating on you or anything, just saying you should have said "I like XP more than I like 7" instead of saying that XP is the best :P