I'd say thus far, my favorite distro has been a debian install I was using for about a year. But you can set up an android dev environment probably anywhere.
A few months back I set on up in backtrack (but that is/was ubuntu based)...
For general use, here's my rough set up -
I generally like a more traditional DE/WM - gnome2 or something similar.
> Terminal Emulator
> Text Editor
> browser (firefox/chromium)
> IM client (pidgin or something - though most chatting now seems to be moving towards web-based).
That's about all I can really think of for what I use most often. I don't do too much with documents, but when I do libre office is nice.
Now for why. I am most comfortable with a traditional desktop...that's what I grew up on. That being said, I'm currently trying out unity on ubuntu 12.04. Most of my use relates towards scripting and web development.