Well presented and audio works too.
However, I'm not sure what the position is with copyright. _ Maybe someone here can explain... the issue is that you are using someone else's characters. Just as Lego will have paid for the Truck design...
Just because they aren't well-known doesn't alter the position (although Lego might welcome the publicity). For example if you chose an Enid Blyton character, Noddy, or Disney . . . their owners would be far from pleased - unless you negotiate a Fee. Same thing applies to Music - unless you're covered it is a bad place to be.
You're probbably aware, vidmanners, that there is a whole world of Lego videos out there and you raise an interesting point about copyright. The same probably applies to films about cars - at least one person currently posting on this forum is making films which do nothing but display the car. But whre does it end? One could argue that shots of a rally are not much different - you're shooting cars designed by someone, on which copyringht exists.
I don't know whether it is generally the case that Lego encourage videos, but I know of one instance where they did. After seeing an entry in a competition by a 17 y/o boy who is local to me, Lego actually commissioned him to make a Lego video. Here's the articl;e:
Teen film maker laying building blocks for the future (From Elmbridge Guardian)
And the film: <a href="http://www.youtube.com/watch?v=Jh-LZFtsDIQ&feature=player_embedded" target="_blank">
Note how he pays attention to detail - especially the lighting (he's posted a coupl of tutorials about lighting which, whilst aimed at "brickfilm" makers, apply equally to full size productions.