For me this is a no brainer. Yes, people should be entitled to commit suicide if they wish. I can think of no more basic right than the right to take your own life. If our lives are our own and not the property of a state or religion then surely we should be able to decide if we wish to end them or not.
Various religions claim our lives in the names of their God's - either to sacrifice in battle etc or to try to deny us the right to end our lives. Personally I'm of the opinion that any deity who wishes to "enslave" their followers, by removing their right to their own life, isn't a deity I'd be choosing to worship.
It may be a selfish act (leaving loved ones, hurting those you leave behind etc), it may be a sensible act (for someone facing a prolonged, painful death), it may even be a noble act (does killing yourself to save the life of others/another still count as suicide?)
Right? Wrong? Good? Bad? Who are we to judge each other on a choice whose consequences are so personnel to the person making the decision to kill themselves.