Howdy Jennifer!
You will love either selection but my vote would be for
Bay Lake Tower at Disney's Contemporary Resort based on a couple of things you mentioned in your question.
The rooms are very spacious at the Contemporary but you will find more space and more of the comforts of home while at Bay Lake. You will enjoy a full kitchen as well as a washer and dryer.
The 1-Bedroom Villa will accommodate up to 5 Guests though you might consider the 2-Bedroom Villa if you would like more room. The 2-Bedroom Villas have 1 king bed in the master bedroom and 2 queen beds and in the second bedroom. There is a queen-size sleeper sofa and oversized chair that pulls out to a bed in the living room.
The walk to and from the monorail is really not too far. You can either walk outside through the lobby or use the breezeway from Bay Lake to the Contemporary.
One great thing about either Bay Lake or the Contemporary is the ability to walk to and from the Magic Kingdom from your resort!
Your boys will love it regardless of the resort you select!
Please let me know if you need any further information as you make your decision regarding your resort. Thanks for your question and have a magical day!!