+1 yay! :) You're active, friendly, helpful (I have seen you answering questions in shout), and I have no trouble believing that you want to be a Helper for all the right reasons. I also think you'd be very capable as staff.
My one issue with your application was the fact that none of your weaknesses were anything to do with personality.
~ @chaos546
This is my only issue, too. If you don't get accepted this time (and I hope that you do!), I would add a personal weakness that you're working on that would have a bearing on your staff duties. I also wouldn't worry about not knowing the ban lengths/times (not really a weakness), because I'm assuming there's some kind of training or staff-only material that details those.
As far as TeamSpeak goes, go ahead and listen a little bit if you need to before working up the nerve to talk. You can type in the chat window to talk to people if you want. They will probably encourage you to go ahead and use your mic, and when they do - or if they don't and you just hear a conversation that you want to join - feel free to say "Hi!" :)