The first D&D movie was one of the worse I'd ever seen; even more so as I'm a fan of D&D. The monsters didn't act like monsters out of D&D, the villains and heroes were all morons, the spell effects whilst OK in places were a bit over the top elsewhere, the magic was either all very weak or of artifact level, there were *way* too many dragons acting very non-dragon like, the plot was full of holes, etc. etc.
In this movie at least the monsters, although there aren't too many of them, act like they are meant to. There's much more of a variety of magic and the effects are good. There's a few puzzles, and outdoor, indoor & dungeon adventures - a good mix. The good guys as well as the bad guys get wounded - and not just lightly. The heroes are also a lot more natural and likable, although still a bit two-dimensional, and the plot is still a bit weak compared to a decently written adventure for D&D, but in comparison with the first film this one is an Oscar nominee. So, overall a decent B-grade Fantasy. If you swore you'd never watch another D&D movie after the first one, it might be worthwhile reconsidering. If only we could get Drizzt onto the big screen...