tkitna, We've had good sit-down meals at Universal at Pastamore, in the CityWalk on the way into the amusement parks. Not great, but good; solid Italian. Jimmy Buffet's is usually packed tight for slightly below average burgers.
Sci-Fi cafe; is that Cosmic Ray's Starlight Cafe in Tomorrowland? McDonald's style cafeteria stuff. Good for kids, used to be pretty bad but now it won't give you heartburn.
Most dining in Universal parks is "eh"; it's edible, won't give you heartburn, but won't bring you back, either. In Universal Studios, Richter's Burgers is ok, cafeteria style McDonald's. Lombard Seafood has good fish sandwiches, but was closed when we were there last week. In Islands of Adventure,
Mythos has won "Best Theme Park Restaurant in the World" for several years running; it's pretty good. The worst thing about Universal and Disney casual dining is the poor line and crowd control; you usually wind up holding a tray of food for a family, with nowhere to go with it. But people make do, and everyone seems to eat.
I'm going to go a little off topic and cut/paste a review I did of The Wizarding World of Harry Potter for a travel forum. It's information worth having if you're considering visiting there.
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OK, here's the skinny.
We arrived at the park at opening. At a reasonable walking pace, we made it to the line, which by that time stretched from WWHP, through Adventureland, through Toon Lagoon; and not straight through, but circuitously, around the edges, with ropes doubling the line back on itself. We hit the line at about 9:10. This wasn't the line for any one attraction; this was the line
to get into WWHP.
(EDIT: The wait in line was almost 2 hours, we got into WWHP at about 10:50.) 
*TIP: When we left WWHP, there was no line. Go do other stuff first, while everyone is in line, go on Spiderman, Hulk, Jurassic Park, all the stuff that's usually 60 minutes will be 25 minutes. Go to WWHP after 1-2 PM. You can save on the Express Passes, too; they are not valid in WWHP, nor on the Rip Ride Rocket in Universal Studios. WWHP is still just as crowded then as it is any other time, but you don't have to wait in line to get in, just at the attractions inside.
Once inside WWHP, it is a cluster, at least now. You will be basically elbow to elbow, shoulder to shoulder anywhere you want to go. Not much attention was places on crowd movement, IMO; on entering, you can go to the left, for the new ride, or to the right, which leads down a cul-de-sac, where 75% of the crowd goes (and then tries to get out of); anyone who isn't going to the left, plus everyone
coming from the left. The shops and restaurants are down the cul-de-sac. The lines to get into the shops depend on where then are; count on 45 minutes (at least this summer) to get into the high traffic area shops.
I found a shop off the the side and waited about 15-20 minutes, but once inside it was elbow to elbow, shoulder to shoulder. It's hard to describe just how bad traffic was in that store. On entering, there is a large display shelf almost in front of the door; you have to go either left, or right. The corridors for either are only large enough for one person at a time. But if you go right, that is also the checkout area. So you have to go left... but that is where the people who are leaving without buying are trying to go the other direction from you. This was a wand shop. You are supposed to get one fitted for you, but people were just reaching for wand boxes, like those old cartoons from the 40s of women at department store sales.
There was a neat display inside, though; a book that bites.
There are two old rides that have been renamed and had the fences moved to bring them into the new park, Dragon Challenge and Flight of the Hippogriff were coasters previously in The Lost Continent. There is one new ride, HP's Forbidden Journey. As you might expect, this is the direction most people go upon entering...
WARNING: Big/fat people (like me) need not stand in line. Go right to the front, try the test seats. If you can't click them shut 3 times in a row, don't bother. I couldn't come within 6" of a click, but I'm pretty big (6'2", 300 lbs). However, you don't have to be real, real big. The chairs are off to the right, behind the crowd in this photo, you can see the top:
Those in the party who did go on the ride thought it was pretty good; they described it as "Soarin' on steroids", where all the swoops and drops and turns are much faster and abrupt. The wait was about 45 minutes, controlled mostly by the limitation on the number of guests allowed into WWHP.
DO NOT attempt to eat sit-down food here if you are immediately hungry! The line to get into any dining area is, I dunno; an hour, maybe? 90 minutes? And even upon leaving WWHP, the closest dining areas were packed. We wound up waiting 25 minutes in line at the border of Adventureland and Toon Lagoon.
The wait for Butterbeer was 45 minutes.
Butterbeer is cream soda with a butterscotch foam applied. A large costs... $10.65. But you get to keep the mug. You get to carry the mug around with you the rest of the day.
*TIP: If you want a butterbeer quickly; go to where the bathrooms are, and there is a small, peaceful patio. There is a door back there into a bar area, and the line was only about 10 people deep. No food served at the bar, though. And there was no one at the patio, either.
I caught the singing frogs, but I was in line at the time and didn't get a picture. Fun a capella.
Overall, to say I was underwhelmed is not quite right; disappointed is more like it. If you are used to Disney, and aware of the differences between Disney and Universal, then the worst of those differences are on display here. Disney are masters of understanding crowds, and they don't funnel people into cul-de-sacs. Their shops are open, with multiple traffic lanes. The most recent attractions, like Soarin', have fun waiting areas. Universal tries to make the experience more immersive, but in doing so they tend to ignore the realities that their "worlds" are set into.
All of this might change, of course, as people get used to WWHP and the excitement dies down. I hope so. But in the end, it really looks like it was designed for maybe 1,000 or so people at a time, not for what we estimated at perhaps 10,000-15,000.
(EDIT: I checked with Mary Joan, she says more like 2,500-5,000 at a time.) If your kids are looking forward to it, go. Do it later in the day, not at the beginning. Skip the express passes, they're not good in WWHP and not needed elsewhere (because WWHP sucks people away from the other good stuff).
And also; we went to Universal Studios the next day, and it was delightful! The longest we waited for anything was 15 minutes for Men in Black, we walked right onto/into almost everything else, including Terminator 3D and The Mummy (the kids rode it 3 times in a row). The line for burgers was about 10 people deep. We saw and did everything we wanted to between 11AM and 4PM, and we were back at the hotel by 6.
They skipped the Rip Ride Rocket; it seemed to break down frequently, didn't take Express Pass, and frankly it looked pretty intimidating to them both; the first thing it does is takes you straight up. It was shut down when we arrived, and during the day there were frequent lapses between cars of as long as 15 minutes. Here it is shut down:
