You'll probably find las Terrazzas less convenient, as you'll need to get backwards and forwards by boat. Walking is quite possible and fun, along the beach, but you won't want to do that many times and not at all after dark. Against that, the resort is classy, has a good dive shop right outside (White Sands), and the area is much more peaceful and "Caribbean" than south of town. I believe they have a restaurant but I'm not sure, but there are several superb restaurants a short beach walk away.
Victoria House is very up-scale, and you will either like that or you won't. I personally wouldn't. It's much more of a real hotel than las Terrazzas, with more facilities, but no dive shop anywhere near. You'll have to arrange pickups with one of the dive shops, and the hotel will do that for you. Again, I'd rather have a dive shop I could walk to, but that's just me. VH is maybe 2.5 miles south of town, at the very end of the metalled road. Road transport is easy, whether rented golf cart, motorbike, bicycle, or taxi. VH is is one of the most expensive hotels around on Ambergris Caye. Up-scale and very expensive bar/restaurant.
Xanadu has always had a good name. It's greatly cheaper than VH, possibly of the same order as lT (that's a guess). It's small and often gets full up months in advance. It now has a dive shop not too far away. No restaurant or bar.
There are many other places you could consider. A few yards along the beach from Xanadu is Caribbean Villas, with a nice beach bar that usually does bar food. They also rent/teach windsailing etc.
Where will the rest of your group be staying? And do you yet have dive arrangements made?
Have a look at
Belize Lodging Guide, Resorts, Hotels, Accommodations, Reservations, Rooms in Belize for more ideas.