Green Bay area
They all play very similar so the real question you should be asking is What theme do you like better? Only you can answer that.. not us.
Castle Ravenloft - Horror, Vampires
Wrath of Ashardalon - Dragons, Classic D&D tropes
Legend of Drizzt - Drizzt and the excellent Salvatore novels
Temple of Elemental Evil - Elementals, classic module
The best answer there. Other lesser points for most people anyways, would be difficulty of the game and the small additions each game brings when made after the previous. Thus the newest one has more than the last.