Universal Orlando...should we get a 4-day base or 4-day park-to-park ticket?

I think that Universal is good for 2 days, 3 at the most. So since I think 4 days is significantly more than you need, I would spring for the park-to-park to hopefully help you from getting bored. But you really don't need that much time at Universal. It is way smaller than Disney.

Go for it! Spend a full day at one park the first day, then a full day at the other park the next day... by that time, you should be able to figure which rides you like best... the next two days you can go to your favorite rides at both parks.

For a four day visit I wouldn't normally say a park-to-park ticket would be worthwhile, but for only $26 extra dollars I personally think it would be worth it for the extra flexibility it will give you.

It isn't that much of a walk from one park to the other, maybe five minutes. Considering there's a lot of walking anyway, you wouldn't be adding that much. And you're right that you could see the WWOHP 4 times. It that's a big deal to you, the $26 might be worth it for that alone. That section of the park gets crammed from about 11 am until late afternoon/early evening. having two extra evenings or mornings would make it much more pleasant. I usually get park-to-park tickets when I go, mostly so I can move around and avoid some of the crowds. More people go to Islands of Adventure overall so it's nice to leave there in the middle of the day and head over to the Studios. Not only are the crowds usually smaller, most of their rides are high-capacity, meaning they can shuffle through lots of people in a short time. If you're visiting in the first half of April that will be important, the crowds around Easter are heavy. Also Universal Studios has more indoor rides/shows and air conditioning is nice in the middle of the day. If your parents are not thrilled by the extra walking, try to tempt them with CityWalk. It's basically along the walkway between the two parks. You can stop between parks and eat and look around the shops. It's a nice place to take a break.

OMG I would be pissed If I spent money on a four day universal ticket. I dont care how much you think you love Harry Potter. There is just not enough at Universal to make it worth spending four days at the park. You only need a full day at each park. AT MOST I can see going for a third day. Universal is very small. The Harry Potter section is one of the smallest sections. I do not know anyone who has been and not commented how surprised how small it was. Its great but still its small. The parks on a whole are very small. I have frequently been to both parks in the same day. A few weeks ago my friend and I arrived at noon and left around 5ish and with the exception of the water rides we rode EVERY major attraction. A couple of them we rode more then once. I know without a doubt your not going to listen to me or anyone else. YOu saying I WORSHIP Harry Potter. I am not like everyone else. I will spend ALL DAY looking at every detail and studying it. Unless you plan on sitting on the wall and staring at the buildings there is no way on earth you could spend all day. You would go so bored. However, you will not listen so buy a four day and see how much money you waste.