dude, take your pick. Val d'isere for awesome nightlife, the best lift-served off-piste in the world, and also one of the best parks in the alps due to its being linked with tignes.
Chamonix for awesome backcountry, but no park. Its also a proper town so if 'urban' is what you want then its all yours, although with mountains like this all round i dont think theres a choice!
For a sweet newschool scene check out deux alpes, never been but heard the park is nice and some good boyz to ride with.
As for the rest of europe - mostly all good, if youve never been then it'll blow your mind.
If you are there for the winter msg me and you can get in on our Alpine cult banter.