All good suggestions. Basic Fantasy roleplay, FATE, and Savage Worlds are the ones I would most likely go for. Plus there is the one I did go for. At first mostly because it meshes/unifies all editions of D&D very well, so all the bookshelves of books I have been keeping for years and decades are all useful again. Since then I have found the SIEGE mechanic to be very flexible and very friendly to house rules.
So you may want to give Castles and Crusades a look. People who discover it often post "after reading it last night..." and being anxious to start up a game/convert over. So I am pretty sure most people would find it quick and easy to learn.
Our boards often have threads titled, "I can't believe how friendly it is around here!" So if you want to check it out and ask questions go to the forum linked to trolllord.com and sign up. We'll be happy to help.