I stayed in a LM room in January and it was about a 7-10 minute walk from the buses to my door, depending on how fast I felt like walking. Some people cut across the parking lots and made it quicker.
I stayed in Broadway at ASMu last October and it was maybe 5-6 minutes' walk from the bus stop to my room, again depending on how fast I felt like walking. The only time I had a shorter walk was at All-Star Sports last August when they gave me a football room and it was so close to the main hall that I never even bothered timing the walk.
I've never stayed at Pop but I'm going to in a couple months and plan to request 80s/90s. I did eat once in their food court when I was at AoA because I was visiting anyway.
I generally only eat at a resort food court once or twice during a trip so I don't really have strong opinions of those. AoA's was good, Pop's was good when I wandered over there, ASSp and ASMu were good too. It's a food court, my expectations are quite low.
Bus-sharing at the All-Stars is nowhere near as big a deal as people make it sound like, either. There are dedicated buses almost as often as there are shared buses, in my experience. It probably varies by season. I also noticed very little difference in transportation time between AoA and the All-Stars.
Here's the point of my post: You're going to get basically the same room with different decorations no matter which one you pick. AoA is going to have the coolest decorations. ASMu will probably be the cheapest. Pop is very popular and therefore probably can't be a bad choice. You'll have at least decent food and transportation at any of them and those factors are so hit or miss for different people that I'd never select a resort based on them. (One person will hate Pop's food, another will say it's the best they've had. One person says the buses at the All-Stars stink, another person says they never had a problem. etc.)