1. mepis/ubuntu (google for them, should be the first result returned)
2. there are superfacial differences between distros, as they are all running the same basic thing, just a different feel in places such as package distribution and file organization.. aimed to make your life easier (Each has their own way), so explore some and get to know them before making a decision
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lisp hacker

running: FreeBSD 5.4 - still learning

develop with: SBCL + emacs for lisp, Anjuta IDE +gcc for c, SPE for python..
browse with: opera