I have a core of websites that I search for good, honest DVD reviews and technical information. They are, in no particular order;
www.thedigitalbits.com www.dvdtalk.com www.dvdjournal.com As of last week, dvdjournal is going offline. Their last post on their website is a great read for anybody who has ever played a DVD. Seriously, it's a good, honest rant about where the home media business is going or not going as the case may be.
While you're there, check out some of their older reviews. I always found their reviews to cover a good summary of the movie, without giving away too much, while also telling you if it was worth your time to view it.
Their leaving the web also makes me feel older since I remember discovering their reviews back in 2000. Kind of amazing to think that's already 7 years ago...