The thing I like with Windows is that it's very easily customisable.
I have mine with a classic control panel and start menu (as I prefer that) disabled UAC (as it annoys the hell out of me).
I love Windows Aero - initially you don't notice the difference it makes like if you leave the mouse hovering over minimised windows you get to see live data which I think is great and the alt-tab button on the quick launch bar is great again with live data being displayed there (by live data i mean you can actually see the movie playing, the download bar moving, etc.)
On my system I also notice that it boots faster than Windows XP the patch management system is much better (requiting far fewer restarts than XP) and encompassing all products (yes I know you can do that in XP but it's not as easy as this).
Again the fonts, for me, are easy to read and like everything else with windows can be turned on / off.
With regards to the Windows 2000 post the reason for not staying with it is blatently obvious. The lack of support for it, which in turn means that nothing is being patched, means your machine will be wide open should someone release an exploit for it.
Anyway thats my 2p worth....