I built the Lego set that I bought last week. It's pretty cool. It's got lots of features on it that I didn't really expect, like an actual working pulley system to pull the drawbridge up.
The dragon that comes with it is also really cool, as are all of the figures. The wizard is especially cool because he's got this really nifty cape.
One thing about Legos though. They are different than they were when I was younger. When I was younger you had to build the walls of things entirely out of Lego bricks. Now, many of those larger pieces are molded into a single piece. It's nice when putting the thing together because it eliminates steps...but it also cuts down on the amount of pieces that come with a set.
In sticking with the Castle theme, I got my second set tonight with a coupon at Toys R Us. It's the Lego Troll Battle Wheel. It's an exclusive item that is found only at Toys R Us. It's pretty cool.