Can a hero declare a battle action, use hustle to move 3 spaces, and then make two attacks? My wife has been holding onto this card for days waiting for me to find out!

Assuming that the effect of "Hustle" is something like "move 3 extra spaces this turn" or "receive 3 extra movement points this turn," then yes, definitely. Declaring a Battle action doesn't inherently give you any movement points, but it doesn't prevent you from moving if you get some (e.g. by spending fatigue, or from an item).

Yes, your wife can do this. The Hustle subterfuge card states:

Play at the start of your turn.

You hero may move 3 extra spaces this turn.

She can even move 2 spaces, battle and move 1 space after.

Ezhaeu said:

That's not quite rigorously true. She can play Hustle and declare a Battle action, and then could move 2 spaces, make 2 attacks, and move 1 more space (or any other permutation of 3 moves and 2 attacks). You can even split up the 2 attacks--e.g. move, attack, move, attack, move. But battling is not something you do some time during the sequence, it's something you declare at the start of your turn that gives you the right to make two attacks during the sequence.

Right. That's what I meant. You state it correcty with the good game terms.

+1 for you