Hey there Patricia,
Welcome to planDisney and thank you so much for this question! My wife and I have two little ones and my son is also a huge fan of Marvel and Star Wars - so I can definitely relate to your question!
At the Disneyland Resort, you'll find
Star Wars: Galaxy's Edge in Disneyland Park and
Avenger's Campus in Disney California Adventure Park. Luckily, they're a short walk across the esplanade from one another so if you purchase the Park Hopper option for your theme park tickets then you'll be able to hop between both parks starting at 11:00 AM each day. This definitely adds a lot of flexibility to a visit and is usually a must-have for my family when we visit.
Depending on your budget, Disney's Grand Californian Hotel & Spa is going to provide the most convenience for your stay and is the most luxurious of the Disneyland Resort hotels. It sits near the end of the Downtown Disney District which means it's a short walk to the entry gate for Disneyland Park. It also has two private entrances to Disney California Adventure Park as well!
The first entrance can be found by following the signs for Disney California Adventure Park from the lobby, which deposits you near
Grizzly River Run. The second entrance can be found by exiting out of the main doors (near the outdoor bell services desk) and walking down the sidewalk toward Disneyland Drive. Right after you exit the pedestrian gate toward Disneyland Drive, you'll take an immediate left and see another pedestrian gate that says it's an entrance for hotel guests. You'll need to scan your room key to open that gate but then can follow the path to this alternative entrance which deposits you near
Seaside Souvenirs.
If Disney's Grand Californian Hotel & Spa is out of your price range, then you really can't go wrong with either of your other two options - Disneyland Hotel or Pixar Place Hotel. Both options can utilize the Disney California Adventure Park entrances I outlined above, but these hotels are also near the Downtown Disney District
Monorail Station, which takes you into Tomorrowland in Disneyland Park.
One additional tip: one of the mornings, I'd recommend starting your day in Disney California Adventure Park and grabbing breakfast at
Pym Test Kitchen. My family and I love doing this and grabbing a table outside to watch for heroes! We typically get a great opportunity to meet at least 2-3 walking by and have really fun interactions.
I hope that helps, Patricia! Thanks again for your question and feel free to come back and see me if you think of any follow-ups. I'd love to help!
Have a Magical Day,
Greg