Stayed at Hilton last year for a school convention. Elevators were always a hassle to get onto and we had to wait forever for them (if we chose to even use them). The rooms were always clean and really well kept. One thing I did not enjoy was the restroom door, it was a sliding one and I was always terrified one of my roomies was going to walk in on me.
The coffee maker in the room was a life saver and you are provided with instant coffee packets every morning (along with sweeteners, cups, etc.).
The walk to the park was not horrible, but after a long day in the parks is sure is not fun. We got the ART shuttle passes because they were cheap and saved time (they were 4 dollars a day I believe and there was a special price for multiday passes). This shuttle was super reliable, but we always jumped onto the marriott's ART ones because they were always less crowded (across the street, got picked up first on the route). Again, not a terrible walk if you are just popping in and out of the parks, but the shuttle saves a lot of stress!
Overall, nice hotel with some dining services inside (little food court with subs, pizza, mexican choices). Little on the pricey side, but you get security and cleanliness for it. (BTW, target is not that long of a walk away and we stocked up on snacks there for the room!)