But see, there in lies a problem that the OP wanted you to acknowledge. Know your limits, know your playstyle. We are all here to have fun, and from what I read here in your post, is that it sounds liuke you won't be able to/can't have fun playing with season experienced players until you feel more comfortable yourself.
Arming yourself with this Knowledge you can make mucher better choices when deciding to join or even form your own PUGs.
And Remember: "Knowing is half the Battle!"