All the parks will be very busy that week
so it really doesn't matter very much which one you choose. The best advice is to "stay loose" and "go with the flow". New Year's Eve will be incredibly busy and you should get to the park early in the day. If you are staying on-site, use Disney transportation. If you are coming from off-site, you'll have to be there by the morning to be sure you can get in before the lots and/or entrance closes.