I can only speak of the Omnibot I'm working on now. I've never hacked something up like I been to get things working correctly. I must have taken the arms apart 20-30 times to get them working correctly. It's been a trial and error to get the right size servos for the wrist to turn, and the hand to open. Then when I ran it across the floor, the hand got caught on something, and out ripped the hand! I never did any kind of programming, so I'm pulling my hair out! The best part is, I've started asking questions, and everyone has been real helpful! I don't think it matters which one you build, I think once you realize it's going to take time, and patience, you'll enjoy yourself no matter which one you start with. I'm glad I did the Omnibot first, because I would eventually like to do a nice Wall-E.

Good Luck!

Omnibot's are a nice project. There is a lot of scope on what you can do to them. Plenty of space inside once the guts are removed too. The original drive motors are great and can easily be hooked up to the EZB with a H-Bridge. Add in servos for head pan, arms, elbows, hands and claw grip. Ping sensors, IR sensors, current monitors, voltage monitors... plenty to look at and gradually get to grips with the EZB and modifying old toys. Plus there are a lot of them about so if you mess up there will always be spares. And loads of Omnibot projects to get ideas and help from. Quite cheap too but prices are going up all the time.

Wall-E is a pretty simple one but it depends how far you want to go too. These are becoming more and more expensive though. Adding the camera to one of the eyes (or two, one in each) is tricky but do-able. Add servos for the arms and head. Change the drive to 2 modified servos. Add in ping/ir sensors. Another popular choice so many in the projects section.

Brookstone Rover is the easiest as the movement is Wifi based so no hacking at all to get that going. It depends what you want to add to it. It's a great platform as it has the camera built in too. Not sure on cost as I haven't sourced one over here yet.

But personally I would start with the EZ-Box Bot. Build one of those and get to know the components and the ARC software. Very cheap as it's made from recycled household junk.

thanks. personally i would like to do the wall-e but like @RichMR2, he's expensive, thats why i was going to make a mini wall-e from the interactive wall-e. The brookstone rover?(if i can't do the wall-e)I would like to buy the top half of a wall-e and hack it away and mount it on top of the rover. The latest thing i found was the R2D2 robots circulating. if they're cheap i would like to do/use one of those.

Nothing is cheap Believe me, before you know it you will have spend a small fortune.