On terms of best movie ever, Citizen Kane is an obvious choice because eveything about it was just so well-done. But I'd also have to put in Silence of the Lambs as one of the best movies of all-time, because the quality of the acting, directing, and writing are amazing, and really mess with your mind to create a near-perfect psychological thriller.
For funniness, I suggest Nacho Libre and Legally Blond, but for merely very good movie I would suggest Simon Berch. Truly touching and you might cry; I love it!