Just to add a few pieces to my post.
The ugly resort in the Trois Vallee is Les Menuires, however is only the centre part thats dreadful, the newer bits are not that bad and its cheap compared to the other high resorts.
Val Thorens is actually quite attractive for a purpose built place with wood clad buildings and gives immediate access to the most snow sure skiing. However on a bad weather day its like being on the moon!, there are no trees at all.
Brides les bains is the valley town and has direct access to meribel via a long and cold gondola ride. Its a cheap bargain base, but a bit dead at night. There is no skiing directly down to it either.
I love the term "carnival"!!! please tell me when, so i can go!. French school holidays last from the 1st week of Feb to the 1st week of March, the paris ones are the worst. A very useful link is, that shows last years at the moment, is www.net4ski.com/calendrier_vacances.htm
The 'numerous' british holidays are staggered over 2 weeks from 9th feb to about 23rd of feb, 2nd week being more popular.
Last season the last few weeks had the deepest snow, in fact it seems if the season is moving later.
Courchevel and Val Thorens tend to have better snow than Meribel, but meribel gives the best access to it all. 2 lifts either way and you can be in courchevel valley or vallee de Belleville(val thorens/les menuires valley)
Be aware the lift map is printed back to front!! and don't get stuck in a valley ie. if in val thorens know when the link lift back to meribel closes, if you miss it it will be very expensive!! as its about 1 hour by road.
Enjoy meribel. Try www.meribel.net
and for snow conditions and historic stuff try www.skiclub.co.uk
Enjoy meribel, but don't go in February!!