If you have not read the book do so. No movie can convey the images Frank Herbert puts into your brain. The complexity of the plot and the internal dialogue are difficult to put on film. David Lynch's version is the best thus far. The SyFy Channel's miniseries was very meh.
I like the Lynch version because I'm a Lynch fan, but even he hates that movie. He didn't have final cut, there were tons of production woes, and the script was being constantly rewritten during filming; hence the version we got. That being said, I still really appreciate the scope of that movie and what it at least attempted to do....but Denis Villeneuve is a visionary director (one of the greats of this current generation: example Blade Runner 2049, another cult classic sequel), and I expect to be awed with his rendition. Especially since he's announced it will be split into 2 films, which is definitely good news, considering the density of the source material (as others in the thread have noted).