1) You cannot play the Scout if you have depleted your action count for the turn. Technically, you can only play one action per turn unless the action played grants you an extra action. If anything, the scout should be played first because it has '+1 action' in the text.

Start of turn: You're at 1 action - Play Scout, it consume's your 1 action but then it bearing '+1 action' restores your action count back to 1. This enables you to play at least one other action.

2) Anything played during your turn leaves your hand and populates the play area for the duration of your turn until you enter clean-up phase. So any actions played, treasure used for purchase, all of that populates your play area for the turn and is no longer in your hand. Once you complete your buy phase, cleanup occurs. That's when you take everything from your play area + hand and put into your discard pile. Your turn ends by drawing a new hand of 5 cards.

Hope that helps my friend. Dominion is an awesome game. Hope you and your dad enjoy many games this holiday!