I can't answer question #1, since I haven't seen that anime.

My #2 and #3 answers are related.  My favorite side character is Mizunokoji
Tobimaro from Urusei Yatsura, since he and I both hate Mendo Shutaro, which
is my answer to question #3.  Tobimaro-kun is very honorable, which is an
unusual trait to be had by any person in UY, while Mendo is a pompous ass
with delusions of grandeur.

James Holzhauer (aka Tobimaro [Ton-chan])
      ---What I like best about Mendo is his sister, Ryouko (That's for you,
Gaffney. ^_-)