Raffles- you can get the ship details from the NCL website. You look under the fleet or ships tab and select a ship... go to the deck plans and the info is on those. But Raoul pointed you to a one stop shop website.
I stand corrected. On the new website, NCL no longer prints the ships "statistics" on the Deck Plans of the ships. I just looked. They USED to have them there. I have not found them on the new site either.
I have been on over 40 cruises all from the older small ship to the big ones and my experience is that the crew, service and amineties make the cruise as well as the ports of call. Some of the older small ships when they were operating were actually better for service than most of the newer ships. So I would say find the ship that has the ports of calls and amineties that best suit you and that way you'll have a great cruise everytime
I use the following website to check out cabin size. www.cruisedeckplans.com. Click on the ship you are researching and follow the directions. It looks like they have all the cruise lines and a ton of information on cabins. Good Luck.