Foundation is one of my favourite sci-fi series of all time. It's at the same time grand and detailed, epic and focused, simple and engaging. Truly brilliant.
Please don't lynch me for this, but I tried to read Dune, and I just couldn't. I forced myself to get about 50 pages in, and it was just far too confusing to follow. The whole family tree, the politics of Arrakis, I couldn't understand any of it. On top of that, nothing significant looked like it was going to take place. As far as I could tell, it was about a kid who became some sort of Arab messiah. I mean, how is that science fiction?
I really do need to try reading it again, perhaps with some more patience. But based on initial impressions of both series, Foundation is better by a mile.
(Former) Lead Moderator and (Eternal) VGC Detective 
