Hi Susan,
Welcome back to the Disney Parks Moms Panel! It's great to hear from you again!
Disney's Contemporary Resort is a fantastic choice! I've stayed there a few times myself, including in the Garden Wing on my most recent visit, and loved being right on the monorail line and within walking distance to Magic Kingdom. Seeing the monorail woosh by in the main Tower building is awesome, but I actually found the Garden View rooms to be much more peaceful and relaxing at the end of a long day. I know you'll love it!
I'm happy to pass on that there are both stairs and elevators in the Garden Wing buildings. You're welcome to submit any special requests before your arrival and you have a couple ways to go about that.
It sounds like you've already made your reservation, so you can just give Disney a call at (407) W-DISNEY (934-7639) to have that request noted. (If you booked using a travel agent, he or she can do this for you.)
You will also have the option of checking in online before your arrival date and I'd encourage you to do that. Look for the option next to your reservation in My Disney Experience 60 days before your arrival date. When you do that, you'll be able to submit up to 2 room requests with your reservation. When I did my on-line check-in for the Garden Wing, the options did include "Ground Floor" and "Near Elevator" (among others), so I'd just choose the 2 that are most suited to your family's preferences.
It's also a good idea to confirm the request during your resort check-in process. I've always had very good luck with special room requests, and while there are no guarantees, it always helps to ask!
Wishing you a practically-perfect and pixie-dusted vacation, Susan! Please visit us again if we can help answer any other questions.
Beth