I have not watched as much Fellini as I would like to. I really need to watch more; for the later stuff, I feel like I need to create the proper atmosphere to sit and watch attentively. Well, for any decent film, really. I find that I watch so much crap while doing two or three other things at the same time, and that's no way to watch Fellini.
Bunuel is a favorite of mine. I particularly like Cet Obscur Objet du Desir, and not just because Carole Bouquet is in it. Have you read the novel that's based on? I believe it's called The Woman and the Puppet, by Pierre Louys. Reading that, and then sitting down to watch the Bunuel is an interesting experience. I also like Le Charme Discret de la Bourgeoisie, and of course Belle de Jour. I've yet to see Un chien andalou, I'm embarassed to say. I heard bad things about the Facets Region 1 DVD transfer, but apparently the Region 2 release is well-done. Now that I'm region-free, I just need to pony up whatever it costs to buy it and get it to the States. Amazon.co.uk, Amazon.fr, and Amazon.de are a Godsend.
Bunuel is fun with undergrads--totally blows their minds. Took my last Film Aesthetics course quite awhile to understand that two actresses were playing the part of Conchita in Obscure Object.