Hello and welcome to the disboards! June will be crowded but its a great time to go. And June is generally less crowded than July and early August. Late hours, parades, shows and rides in full gear. The best thing to remember is to get to the park 30 minutes before opening every day. The mornings are wonderfully uncrowded and you can get so much done. Also, as an onsite guest, you will be eligible for Early Entry each day its offered. On EE days, certain rides in Fantasyland and Tomorrowland are open. But you eihter have to have a park hopper ticket with EE on it (most park hopper tickets have one EE day attached to them but only one) or staying at one of the three onsite hotels. Since you are you will be able to do this each day its offered which is a huge perk of staying onsite. When you check into the hotel verify with them what days it will be during your stay. After spending a morning at the parks, you can take a midday break to relax by the Neverland Pool, have a nice lunch in Downtown Disney or take a nap in your room while the crowds and heat are at their highest. Then you can return refreshed and rested to the parks in the evening. This is what we always do and it works out very well. And allows us to have some relaxing times as well as lots of fun in the parks.
The Finding Nemo Submarine ride is set open sometime in June as far as I know. That opening has changed a few times, but last I heard it was June.
I happen to love June at
Disneyland, in fact I will be there in June and staying at the DLH as well! I think you will have a wonderful time. Just remember to use fastpass wisely and get there early.
The DLH is lovely, it has nice lush grounds, two nice pools and some fun restaurants. You could do a fun, energetic character meal at Goofy's Kitchen or a nice sit down meal at Hooks Pointe or the other restaurant (used to be called Granville's now its "55" something). I would click on the brown links at the top of the page for information on the hotel, dining around the hotel and parks/DTD and other helpful information. Have fun with your planning and congratulations on getting married!