You may wish to look at:
Bodysgallen Hotel - fabulous historic building, gardens and spa etc, the top notch place to stay and only a couple of miles away from Llandudno and about 4 miles from Conwy.
The Groes Inn - about 3 miles South of Conwy. Oldest licensed inn in Wales (or some claim like that). It is often used by car clubs etc and is used to having supercars outside. Generally a good homely atmosphere with good food and drink.
Deganwy Quay Hotel - half way between Llandudno and Conwy. Modern hotel with all the spa facilities located on the river and next to the marina. Some nice places to eat in Deganwy within walking distance (10-15mins walk).
Llandudno is pretty but personally I think that once they have seen the sweep of the promenade and driven around the Great Orme they would be better off heading out a few miles to the walled town of Conwy (a World Heritage Site with a wonderful castle); the harbour area is nice as well.
The Castle Inn in Conwy is also not a bad place to stay as it is right in the centre of the town, it has a car park at the rear but access is a bit tight.
A lot of the hotels in Llandudno cater for coach trips and it can feel a little like a pensioner's club at times.....
Good luck with the choice!