We stayed in King of Prussia/Valley Forge. Lots of hotels, HUGE mall, lots of restaurants. If you are into Revolutionary war, Valley Forge is right there. We rented a car, and I feel that is the only way to go. Our hotel was about 30-40 minutes from the airport, and about 15 from the testing site by car. I'm sure taxis are available, but do you want to be dependent on someone else the morning of the test?
I wouldn't suggest staying at the hotels suggested by the AOA. Neither are truly "walking distance" unless you are looking for a nice 20 minute hike next to a busy street the morning of the test. Besides, you are going to need access to booze (and lots of it) after that freakin' test. Just get ready AND REMEMBER:
NOONE WALKS OUT OF THAT THING AND SAYS... "MAN I TOTALLY PASSED THAT!"
Good Luck!