Each area has its own charm and I really got a kick out of the mushroom caves in the forest. When you enter the cave, the music switches to a Marley-esque reggae tune and Vikki can get really 'high' when she jumps into the air from the shrooms. Also, everything is really brightly colored and very tripped out looking. Its good for a laugh for adults, and kids probably won't see it as much more than a neat looking cave. There's also a cool spaceship area that reminded me a lot of MDK2.
The music and sound effects are spot-on. Each tune befits its level perfectly and all are very well done. I never grew tired of listening to the music whether it was one of the thumping jungle beats from the prehistoric world or the eerily lilting tunes of the medieval area. The sound effects were also quite well done, with the exception of the sound of Leo getting injured when you were playing as him. It sounded a bit too much like Sarge for my tastes. I even really enjoyed the voice acting, for the most part. Yes, Brigette is a bit overdone, but her character in general is quite over the top, so it works. I could swear Vikki's voice is one and the same as Dorothy from the Wizard of Oz, but maybe I just need more sleep. She does make little quips all throughout the game, and although some are lame, for the most part they were cute.