As with most kids, I didnt realize Doom happened before Raiders, because honestly, there's no reason to think it did. Really the only order you HAVE to watch them in is make sure you watch KOTCS last, haha.
I always wondered why Indy never fought the "zombies" in the tomb that were attacking Marion
I was a foolish child.
I questioned why Indy's hat disappeared at the end of Raiders and was a bit bummed out by it.
I never caught the petroleum line in LC, so as a young child, I thought for a brief time that water was flamable.
Before such concepts occured to me (aka, when I was like 4), I thought the scene in LC with Elsa and Indy making out in his room was them fighting, because she bites him.