If the way my son got used to Eastern time is anything to go by, in just a few days your kids will be totally used to Pacific time, and the mornings won't be so bad.
If you're going to play in DTD, go to the part AWAY from the Grand's rooms...there are rooms just up from the DTD stores, and we *could* hear things from DTD even with the doors closed. Don't want to wake up the pacific coasters!
Wind is a big safety issue for fireworks at DL. Unlike WDW, DL is built right in the middle of a city. If the wind blows the fireworks too far to one direction, there is a freeway. Another direction, people's houses. Another direction, into the crowd.
Exactly what I was going to say.
Because everybody built around DLR, they have to watch the noise and safety etc, so they don't cause problems in the surrounding neighborhoods.
Even kids who don't know a certain thing can enjoy the thing for what they think it is. Jedis are immensely cool (sit AWAY from where Darth Maul can come near you, though, he's scary!), the Tron stuff is really neat to the eyes (DS is 6 and he thought it all looked VERY cool, with the lightcycles and colors and neon-ish stuff, well before he saw the first movie (which I'm still not sure was a good idea)). And dancers are dancers, and kids love dancing.
Here's my DLR-vet WDW annoyance! We went from 11/30 to 12/17. It was FREEZING. I'm still getting over whatever it is I got there, just now getting my voice back (it's been gone since the 16th). We didn't get to do anywhere near what we thought we could do, because it was so bone-chillingly cold we just lost body-power! I can't even think about our night seeing Illuminations without almost crying, it was so cold. I didn't get to see Wishes. Or MSEP. UGH.
Disappointments happen at Disney parks b/c things happen. But here I am, writing my trip report slooowly (you just got more info than I've gotten to in the report yet, LOL) and thinking about the next time...
DLR will be just fine for you, and the short hours will allow you to get your rest without feeling guilty that you're missing this or that.