We've cruised three times with
Royal Caribbean and loved it! I highly recommend cruising with them. The only problem we ever had was having a cabin right above a crew cabin last time and the crew member would get in about 2 a.m. and turn on the radio -- we were offered the chance to move, but since we only had a couple nights left and my husband had all of our stuff unpacked (would have had to pack it up, unpack, just to pack again in a day or two) and the cabin offered wasn't an upgrade, it really wasn't worth the trouble.
Don't know if you've cruised before, but it's really great -- very relaxing.
IMO, Royal Caribbean is a class above Carnival. I'd put Royal Caribbean, Norwegian, & Princess in the same class. The kids programs are great -- can't wait till my son is 3 and potty-trained so we can go again!
If price is an issue, pick an interior room rather than an exterior -- a tiny little portal is really expensive and you're never in your room unless it's to sleep or change. Pick a cabin in the middle of the ship -- toward the back you get engine noise and in front can sometimes hear the anchor (tho those rooms can be cheaper for those reasons). Also, I now suggest getting a room that's two levels or more above the crew cabins.
I've used
www.cruise411.com before for information and to book cruises and been very happy -- their prices are very competitive.
Best of Luck,
EthansMom