I have done this several times for both my family and friends that are first timers to WDW. Usually you can get the disney florist number from the concierge and see what they have available. I have had a basket of goodies delivered and it was really neat. It had all sorts of snacks from Disney. Shaped pretzels, rice krispie heads, those yummy mints in a tin, etc. You just have to see what is available.
For my wifes b-day (we were at GF concierge) I had a bouquet of flowers, cake and autographed Minnie pic in the room when we got back. They didn't even charge me.?.?
Most of the time you need only ask and as is known at WDW, the staff will do all they can to make magic.