I consider how much "park time" vs. "pool time" we are going to have, as well as which parks we want to be closest to. We prefer moderate and deluxe resorts based on theming, activities, bed size, and location. Price plays a role as well, once we have it narrowed down to a few contenders. Often we are planning trips with 1-2 months notice, so there are also limitations with what is left available to us.
When we've done quick vacations that were packed full of parks with little rest time, we knew the resort was just going to be a bed and a shower for us. We didn't even visit the pools, so on those trips we didn't choose deluxe resorts with loads of activities. We have chosen DVC rooms when we wanted to spend more time in the room, wanted a "living space" for various reasons, kept loads of food, and needed a washer/dryer unit. Twice I've planned a trip solo with kids and chosen a resort solely for what activities we could occupy ourselves with at the resort when we are taking a day(s) off from the parks. When the kids were a bit younger and we knew we'd basically be sticking to MK and EP, we chose Contemporary for the ease of the monorail. I was solo with kids for part of that trip, so it was nice to be able to get to/from parks without having to break down the stroller. Since our first trip to Disney, we have always felt at home at AKL, even though it's farthest from everything but AK. For one of my "solo w/ kids" trips I embraced the location and decided we would spend an extra day at AK so we could enjoy more and the kids could take more time to get the wilderness explorer badges. AKL has TONS of things for the kids to do, both free and paid, and they love doing the bead activities and trying to get all their beads before the end of the trip. Plus the option of using two fantastic pools and a splash pad make it a good choice for us when we are planning a lot of down time.
ETA: To respond to your comment about "where to spend the money" - We feel that Disney is more an experience than anything, so we know there isn't much to show for what you've spent once it's over. We want to enjoy the experience, and sometimes the hotel plays a large role in that. Once we had visited WDW a few times, souvenirs really had little meaning for us. I might buy a mug every other trip, and the kids want to purchase things, but other than that we don't really spend money on souvenirs. We have a few table service restaurants that are now our "must-go" favorites, but otherwise we are content with our favorite quick service food options and a drink or two at the pool. Because it's so hot we graze on snacks more than fill up with large meals (though we do love a nice siesta in the A/C restaurants). For us, I don't think the food or the souvenirs would be an overindulgence either way, so it doesn't totally affect our room selection (except that our favorite meal on WDW property is always at Sanaa in AKL).