Eragon. Would be great movies if they did it right.
Crappy books don't normally make good movies.
I would like to see the Pendergast books made into a movie or series. They made Relic, but they cut him out of the damn movie.
Zelazny's 9 Princes in Amber would be great, but good luck getting the rights from the estate. After the abortion that was Damnation Alley, they kinda pulled the plug on that one.
I would like to see Tin Roof Blow Down made.
Piers Anthony's Xanth books and world as a kid's show with great animation would be kickass.
American Gods really needs to be a movie, but Gaiman hasn't done really well in the movie business--Coraline being a notable exception.
Oh...and Tyger, Tyger (The Stars My Destination), but that shite is flat out unfilmable.
Richard Kadrey's Sandman Slim books.
The Monstrumologist series would be cool too.