I've been that week many times. It's busiet near the holiday,then peters the further you get from it. If you can stagger a little into non-vacation week time - you get lower crowds those few days.
higher crowds menas more park hours. WE've always been abelto see everythign, but then - we are able to use late and early hours. that helps.
Liekly you won't get much rain, but it also MIGH"T be too cold to really swim or wear shorts. Then again, the most common weather pattern we've seen was where it was cool in the am/pm and warm in the afternoons. for us- that means most days we wear shorts to tour, but a thick jacket in the morning. Around dinnner time, we go back to the resort to get long pants and maybe hats/gloves. a few days we wear jeans all day.
Usually there is at least ONE warm enough for swimming- but that may be all you get. So being flexible is good.
Also.....well....if you are undecided about your resort- it is worth the money to consider the Contemporary and or the Beach CLub/YC/BWk or Swan/Dolphin resorts. I especially like CR that time of year. No matter how cold it is- you can walk from MK to CR in about 15 minutes - an MKhas the most late night hours. similarly the BWK/BC area resorts are only a 15min walk to BOTH HS and Epcot.
However, if you pick CR- limit your WS dinners. It is along trek from Japan to CR via monrail -with lots of stadning on cold monorail platforms. If you pick CR- you can eat at any monorail dining in minutes with almost no outdoors exposure. (The CR monorail platform is indoors.) Of course that's assuming the monorail is running!
Another bonus of CR is seeing the MK fireworks from the resort.
My least favorite Feb resort pick is the BIG moderates - like POR, CBR, or CSR. They have lots of walking outdoors. If you aren't doing a deluxe, then preferred location (at a value) would be my next choice.
Alos, if you are goingto have a non-park day - Presidaent's day itself might a good day to set a rough plan for your non-park day (weather permitting). Another good idea is to avoid MK on the holiday, and use the holiday day to do lesser attractions- like Ellen's Energy and Mexico.