Just to be clear...
Can anyone perform 2 move actions and thus double their speed value?
ie: speed for a hero is 4. So the hero performs move action and moves 4 spaces. Then for the second action, hero performs another move action and gets 4 movement points again?
Yes. You have 2 actions, and none of them have to be any specific action. You just can't use a special ability twice in one activation, or attack twice (unless you are a Rebel Hero in the Campaign). You could move twice.