I have used alot of different bug tracking tools and Bugzilla is actually pretty good for simple bug tracking. Installing really wasnt too difficult- Windows is a bit trickier.
Issues I have had:
didnt see easy way to control classes of users from performing certain actions (like having a developer close a bug)
not being able to create global queries. (I worked around this by creating the query and then, doing some manual inserts in the DB to allow other users to access it as well.)
not very good release management integration. no easy way to create release numbers to have dev mark bug fixed in / bug verified in. (worked around this by creating keywords, but this was hard to maintain)