I personally think respect is the biggest thing people want around their threads/posts being posted sure noobody is perfect and nobody always has a perfect post but if you don't like it then don't post an reply on it this may avoid flaming being made and what not and also that just to help someone is good you can help him fix his problems on his own in the future.
I would enjoy staying on a forum that has a welcoming and friendly community, and also has a wide range of topics to offer. There should be something there to keep people interested and involved too.