LL does rent strollers - right as you come in, on the left. They're singles only - no doubles. I haven't done LL with a stroller, but in general the paths are plenty wide for double strollers and there are out-of-the way places to park them next to major attractions. The only place that I can think of that's tight is miniland, but your kiddos are going to want to be up close and personal with the exhibits. If you have it, I'd bring it. LL also has some rolling hills and quite often there's no shortcut from where you are to where you want to be.
Our favorite place to eat is Castle Burgers - which has pretty much just burgers! It's next to Dragon.
How tall is your DD? LL can be tough for the under-40-inch set. In general, though, I can think of a short-person ride near to every big-person ride - Project X has Cargo Aces, Dragon and Knight's Tournament has Royal Joust.
Don't overlook some of the more unusual attractions - DD likes to build/race cars and Build and Test (Imagination Zone, first thing on the left in the 'stripmall' past AquaZone) and there's a duplo play zone right in the same space.
Don't miss the Firetruck challenge! Your whole family can play - you race to get the truck to the building, race to put out the fire, race back to the fire station.
The Hideaways is also good for free-form fun. DD can play in there forever. The play-thing outside Lost Kingdom Adventure is fun, too, especially if one of the parents is a good sport and doesn't mind being used for target practice.
Treasure Falls is THE lamest log ride known to mankind. Bar none, and I've been on a lot. Well, I haven't been on that one; I refused and DD and DH waited 45 minutes and told me it was as lame as it looked. One short loop with one short drop.
I won't wait for Kid Power Sky Cruisers. We did it once, that was enough. So not worth an hour wait! Besides, I think it's only friendly for pairs. The Kid Power Sky Towers are more fun, for me, anyways, with a 15 minute wait. Also only pairs-friendly.
In general, I've found that (1) summer weekdays, the park is pretty full in the mornings and empties out around 2-3 due to summer camps day trips, and (2) when there's a special event and/or fireworks it gets so crowded you can't walk starting about 90 minutes before the 'party' is supposed to start.
Also, watch your time carefully - LL is quite often open only 10-5 until summer starts and waiting can eat up most of your day. The rides, in general, load slow which leads to longer, slow-moving lines.
Have fun!
Deb