I just came back home from the Star Wars marathon. We started at 12 and decided to end after 5th episode (we became too tired).
Did you know that cutting hands using light sabers was quite popular? Each episode results in few hands cut and Anakin Skywalker/Lord Vader had worst luck — right hand cut twice (episode II during fight with Count Douku and episode VI during fight with Luke Skywalker), left hand cut in episode III (by Obi-Wan this time).
Such long marathon is exhausting but also fun — lot of discussions during some scenes, between movies etc. And it is important to have big screen — we were using video projector so the picture was big enough to watch. 5.1 sound would be also nice to have but stereo sound (like we had) can be also good.