If by "musical theatre" we're using the strict definition of musicals (rather than including plays that merely have music in them), then that's not exactly my favorite genre. Otherwise, I do enjoy the occasional song-and-dance interlude. A recent favorite of mine (recent = within the last five years) is The Producers. Utterly insane, but in a good way.
I've seen a lot of plays, although I haven't been to many big productions since my parents moved. The one exception was Phantom of the Opera, which we saw during the NYC part of my summer vacation. That was truly extraordinary. My only gripe was that there was a little girl and her father sitting directly behind me, and they talked straight through the entire play while eating crunchy food that they snuck in. I've never seen my mother as angry as when she whirled around halfway through and threatened to have them thrown out. Funny and scary at the same time.
And I did get to perform in a couple of high school plays, although our school was so minuscule that we really we're equipped to do so. The English teacher (who directed them) actually begged me to be in the annual production during my senior year; I didn't want to do it that time because I was busy, but one of the actors quit and they had to find someone who could get into a role fast. As it was, only I and another guy actually remembered the script; multiple times we had to improvise prompts for the others to help things progress.