Le Meridien is very nice; superb location and close to everything you need; parking is great;

Plaza Boscolo Nice is very close to Le Meridien; 4 stars and nice rooms; stayed there 6-7 years ago and rooms a little dated but classy. Close to parking if you rent a car and taxi station close by.
Both the Meridien and Boscolo are very close to the bus that comes from the airport (depends on your parents age)

Best Western West End is a nice property; my brother stayed there with a room facing the ocean and his family really liked it; a fairly good property in the Best Western family; During the winter it tends to be inexpensive; it is a few blocks from the pedestrian zone.

In the winter it gets dark early and the city is not nearly as alive as it is in the summer time; you will find that even though restaurants are open, Nice has a feeling of emptiness after dark.