I think it is wonderful! Just look on the schedule when you arrive at DLR. If you do a package, you will get a ticket for preferred seating...if no package, just arrive about 20-30 minutes prior to the show, depending on the season.
I agree with your friend. It is a really fun show, you should see it at least once.
Getting seats is pretty easy, just look up the time that it is playing, and show up. I'm not sure how early you need to show up. It probably depends on how busy the park is. When we went, we had PS because we booked through AAA. Maybe someone else can give better advise on the timing.
I always heard that its recommended to line up 30 min in advance, but I showed up 15 min before the show time and had great seats a few weeks ago. I think it's a must do. It's almost an hour long and is fantastic! If you've ever seen or heard about the Lion King on broadway it's similar to that as far as things moving down the isles and stuff. Genie is hilarious! Enjoy!
It's a Broadway quality/scale production, and as previous posters have said, you don't need a special ticket to get in...just show up 1/2 and hour to 15 minutes before showtime. You won't be disappointed!