I've stayed at Grosvenor a long time ago, we were in a room in one of the wings that opened to the outside. It was o.k. Room was old.
I've stayed at the Wyndham Palace which is now the Buena Vista Palace. It was very nice, very clean and had a nice pool area. There have been some good reviews lately, since the hotel has renovated all their rooms.
I've stayed at the Hilton Downtown Disney as well, 2 times off of Priceline, also a very clean, nice hotel, nice pool area.
If you go to MOUSESAVERS.COM you can read a trip review/report of the Hotel Royal Plaza since the renovations.
Hope that helps!