Hi,
When making a list of people, it's considered proper to put yourself at the end. Politeness, I suppose. So "you and me", "my friends and I", "my brother, our father and I", etc.
As for using I/me, Richard's given a great way of working out which is correct. :) For the grammatical nuts-and-bolts, use "I" for when you are the subject, and "me" for when you are the object.
I will go to the mall. (subject!)
My friends at the mall will meet me. (object!)
Native speakers may sometimes speak their own language sloppily, so it's a good habit to remember what you hear may not always be "correct", or even good.