You didn't say when your trip was -- we stayed at WL during the first week of December (this month!) and boat schedule at that time had the boat to the Contemporary starting at 7 a.m. and the boat to MK starting at 8. So, we hopped the boat to the Contemp. at 7:15 a.m. (the boat runs back and forth all day, in roughly 10- to 15-minute intervals). We walked through Contemp to 4th floor monorail station, rode the monorail to MK, and were at the gates for our Crystal Palace 8 a.m. breakfast by 7:45 -- gates weren't even open yet (barely a 5-minute wait).
This was an easy, lovely way to go and I highly recommend it! Buses for all early character breakfasts are also available -- check on start times when you check in at WL.