That's a very difficult two questions. I don't think people give Leonard enough credit, he's a great character. Sheldon obviously is amazing, he makes the show, but I think Leonard edges it for me. I think he's very cute, too. He's my guilty pleasure
As for a favourite episode, I'll have to get back to you. I really can't make a decision, I laugh out loud at every episode
I've given up downloading the episodes after my computer decided to go crazy on me & my internet provider got a little annoyed at the amount of stuff i download..
So now i am going at E4 pace. Don't mind it at all.