I cruised the Carnival Fantasy in 1996 when I was 21 as a college graduation present. I had no problems with the ship whatsoever!! I thought the ship was beautiful, I don't remember having trouble finding a deck chair, the kids weren't too annoying, the service was top notch, there were no strange or bad smells, and I thought the food was really good! I have particularly good memories of an omellette I had at breakfast, and the large prawns at dinner.
These people who complain of the food must come aboard expecting something out of lifestyles of the rich and famous or something! I would describe the food as much higher quality than your basic american restaurant chain like Chili's - but maybe not 5 stars - I have discriminating taste, and I thought the food was pretty decent.
The only things I would say to keep in mind: Don't feel like you have to go to every meal when there's so much to do onboard. And there is quite a bit of walking involved b/c the boat is big! (I personally like that b/c it helps you walk off all of the food!) Have a great time and don't let these sourpuss reviews stop you for one second!