We all have many emotions, and they're all an essential part of life. You can't fully appreciate joy without knowing sadness. Kids and parents should communicate honestly and openly to each other about how they're feeling, even when it's hard. Family and friendship help make us who we are. Don't try to be something you're not; love and accept who you are. Teamwork and imagination can solve the most difficult problems. Running away doesn't solve anything. Additional themes include compassion, perseverance, and teamwork.
Infrequent use of insult words like "shut up," "moron," "barf," and "dumb." Anger makes references to knowing a curse word; there's one bleeped moment where it's implied he finally said it.
No actual products within the film, but tons of off-line marketing/licensing tie-ins, from books and apps to a wide variety of toys, clothes, home decor, and much more.