The theatre for Fantasmic is not the parade viewing area. It is a huge amphitheatre where the Fantasmic show is put on either once or twice per evening depending on when you go. The Fantasmic show is a mix of fireworks, characters, special effects and a storyline that should not be missed in our family's humble opinion. In the 3 trips we've taken since 2000 we haven't missed Fantasmic. We've done the Fantasmic dinner package twice to assure we get seats even 30 minutes prior to the show. (Check the boards for more details on the Fantasmic dinner package at 3 MGM restaurants). Even without the dinner package, you'll get seats likely, even last week when it was busy, people were getting back seats 30 minutes prior to showtime or less.
As for the MGM parade, we keep missing it due to weather or whatever, but it runs daily at 5:30 and the route is mapped out on the MGM brochure you'll get when entering the park. It's characters on cool cars/vehicles and it should be good!
Enjoy MGM - it's a favourite park with my 8 and 11 year old! Just try to get the showtimes organized so you don't miss things and fastpass Rock and roll rollercoaster - still my 11 yr old son's favourite ride out of all the rides at Disney and Universal.