Yes but the boat stops at the YC, BC, BWV/BWI and the S/D.
Depending on the show times would depend if you could catch both shows. Illuminations is usually 9:00 or 9:30 depending what time the park is opened until. Fantasmic times vary as well.
If you catch an early Fantasmic (7-7:30) you should be able to make Illuminations depending on how much time it takes to get out of the show and board the boat. It's about a 1/2 hr once you board the boat from MGM to get to EPCOT.