I saw some of it, but I can't explain why I didn't like it as well. Some of it wasn't suitable for our son and daughter; too overtly sexual, if I remember correctly. The movie didn't stress that, and we've watched it with them. Our son was bored because it was so long, but he was only 10 when he saw it. Our daughter was 12 at the time, and she liked it better. She's now going on 15 and is the other Tolkien geek in the family!
I think I liked the older movie better because of the visual pull of the Art Deco feel, though I'm not a real big Art Deco fan. There was just a richness about the look of it. I like the actors playing the parts; Jurgen Prochnow, Francesca Annis, the guy who played Paul who's name escapes me right now, Sian Phillips as the Reverend Mother, Linda Hunt as the housekeeper, Richard Jordan as Duncan Idaho, Patrick Stewart as Gurney Halleck, and Max von Sydow as the Geologist (and the Fremen girl's father). Kenneth McMillan as the Harkonen guy was great, too. I thought Sting's bikini was a little over the top, but his was a good, though short, portrayal of the young Harkonen.