Hi,
This has been bugging me for ages and can't remember what it was called.

I don't think it was on TV but was a video and there was this cartoon city and every so often this either purple or green block would come down and cover the city and whoever was in the block went into a virtual world and had races and stuff.
There was a girl and a guy and they went about on hover things. And there was this blue bad monster thing who lived in a tall tower thing.

PLEASE HELP! Its so annoying me! :)

Reboot.