When you're suggesting something for people to do in a casual conversation, you ask "You want to ___?". The words "want to" are often pronounced "wanna" in this situation.

A more formal way to ask this question is:

Do you want to rent some movies?

This would be a better way to make a suggestion to someone you don't know very well. An even more formal way to ask this question is:

Would you like to rent some movies?

This would be a good way to make a suggestion to someone you don't know well and who is older or higher in status than you, like a boss or teacher.