whats that star above my name which says 7?

after you reach 100 posts you will receive a star. the number is your rating. If you post something or respond, there are three rating options in your little discussion box. they are +-!. If someone rates you + your star number goes up, if someone rates you negative your star rating goes down. the last choice is abuse, where you report someone who might be spamming or abusing the forum etc. Hope this helps