My oldest daughter (8 years old) has read the first four Harry Potter books. She loves them and has been begging for our next vacation to be at Universal Studios. I have been pricing it out, and honestly am quite shocked by how expensive it is. For some reason it seems like I get a better value at Disney.

I need some help with planning and have a few questions:
1. Does Universal ever have any good discounts that I should wait for?
2. If we go during a slow season (like the beginning of December or January), how necessary is the Unlimited Express Pass? Essentially, do I need to pay to stay at the hotel that supplies that, or will lines be low enough that it isn't needed.
3. I stayed at the Sapphire Falls Hotel for work earlier this year. I thought the boat system to the City Walk and park entrances was fantastic. But only the 3 most expensive hotels are on that boat canal. If you stay at Cabana Beach or the new Aventura hotel, what is transportation to the parks like?
4. Are there any "must-do" restaurants. I think my kids would be pretty intrigued by the Chocolate Factory.
5. Does Universal have any airport transportation? Like how Disney has the Magical Express?

Thanks!