My pleasure!
I don't think you can get much use out of the advanced search options. Try this: after you search for a video, let your cursor hover over a title. A window will pop up with the title and will often contain other information. This additional information is what is needed for advanced searching (I think). You will often see type, height, and width, but you will not usually see the categories that you have mentioned (stars, rating, etc.)
Are you looking for specific movies? If so, just put the movie title in the title box and search. You can also try just searching part of the name (if several words).
If you are looking for movies with certain actors, try typing the actors' name in the title box and search.
Hope this helps