With preferred, you can request either Congress Park or Springs area. Besides things noted above, Congress Park can result in a room that has a nice view of the large lake looking over to Disney Springs. As a result, if you have a request put in for Congress Park, you might want to add a request for higher floor.
Congress Park has a pool, but it is just a pool without a theme and no long slide into the pool or a drink/quick food bar-like store. Springs has one of the two main large themed pools with the extras. Thus, if it is important to you to be very near a themed pool, Springs would be the choice.
The SSR bus service to the parks has five stops, in order by designated area: Grandstand, Carousel, Paddock, Congress Park, and Springs. An issue that can sometimes happen during the morning rush hours with Springs, but less of a risk with Congress Park, is that the bus may be full or have standing room only when it reaches Springs.
Springs has the advantage that you go directly to the park from there but the disadvantage of being the last drop-off coming back, but Congress Park has the same issue with three stops coming back before it. Just note that I have never found the SSR buses to present any significant disadvantage as to other resorts. The trips are still fairly quick and there are usually no significant waiting issues (except for that which can be suffered by all resorts using buses when departing a park at closing time, when the lines to get on a bus can be far longer than the number of passengers needed to fill a bus).
As noted above there are those that prefer just driving to the parks. I recommend not doing that for MK simply because that driving trip itself can be quite a challenge. Once you are in the huge parking lot, you must first go by tram or walk to the Transportation and Ticket Center area and then wait to catch a boat or monorail to MK. Moreover, particularly during morning rush times, the traffic back-up to even get to the parking lot can get very long. The total trip from resort to actual park entrance can approach an hour. Also, I do not know if it is still an issue, but it was in May, there may be no trams at Epcot or Studios to take you from your parking space area to the park entrance -- they did away with the trams during the pandemic and they had not yet returned to Epcot and Studios last time I was there, and thus you could have long walks from where you park to the front gate.
The walk to Disney Springs (the big mall, restaurant and entertainment center, not the Springs area of SSR) is fairly long from the SSR Springs area but still doable. Congress Park provides the shortest walk, but even that has some distance to it, and you enter Disney Springs from one end of it, and thus walking from one end of Disney Springs to the other end of Disney Springs, such as to get to Cirque du Soleil, is itself a long distance (about 2/3rd mile).
