I'm with you on the startup slowness on some machines. I tend to just leave it running all day once it starts (although to be fair, everything is slow on the particular machine I'm talking about).

As far as the ALT+TAB problem, I haven't noticed that myself. I'm running under XP most of the time nowadays and haven't seen this. I don't recall having to do any special tricks to make this work. I know that doesn't help you, but "works for me".