You should have no problems taking the bus for either reservation. For both, you'll need to take the MK bus. For Chef Mickey's, once at the MK, either walk across the street (please use designated walkways) or hop on board the Monorail. Both take about the same amount of time.
For CRT, I'd be out at the bus stop around 8:15. For CM, I'd be out a little earlier... It won't take that long to get there... these times would be "worst case scenario" and most likely, you'll get to both with PLENTY of time to spare. It's always best to be early!
If you do however choose to drive, estimate the same amount of time. For CRT, you'll have to park at the TTC, walk or take the tram, and then take the Resort Monorail to the MK.
For CM... if you plan on spending the day at MK, park at the TTC and take the Monorail. Otherwise, park at the CR... they'll give you a 3 hour parking pass. After you're done, you can go to wherever you want to go.