hey jkerns,
how would you rate the lego mindstorms nxt 2.0 against building a wheeled robot like jcmatos has put together here for someone with no experience in robotics?
http://www.societyofrobots.com/robotforum/index.php?topic=15464.0
The Lego in the video was pretty much just a cookbook build from a set of instructions, hack a little C code, and it is up and running in a couple hours.
The robot that jcmatos did would require a lot more effort, design and creativity. And, you would learn a lot more.
Which is best for a beginner? Depends on what you want to do. You can get creative with the Lego, but you can also just "plug and play" with little effort or knowledge. But if you want to really learn how these things work, then a scratch build would be the way to go.
I don't want to run down the Lego stuff - if you want, you can have a lot of fun building some real clever, original, stuff - but you can also just look up pre-existing designs and copy without learning as much. I did the one in the video so I would have something moving around the table when we have "show and tell".