Hi Coleen
The Athenaeum is on the New Ross/Wexford side of Waterford - its just outside of the city but would be approx 30 mins walk to town.
The Fitzwilton looks nice, have never been in it myself but don't think there is parking. It is on the far side of the quay.
The Tower is on the other side of the quay - abit outdated at this stage in my opinion, there is a car park at the back and it is in a nice location, central for the Castle, Faithlegg etc.
The Granville is the most central, on the quay. There is parking opposite in the main car parks (not sure if hotel reimburse for parking). Lovely hotel and food in the restaurant is gorgeous.
Dooleys Hotel is also on the quay. Check out the Woodlands Hotel - its out the Dunmore Road, v. close to Faithlegg / Castle but you would have to get bus/taxi to town.
My recommendation is the Granville!