When choosing a TV for your Recreational Vehicle, the size is often the most important consideration. Because of the limited space in an RV or camper, smaller is generally better. But, of course, it has to be big enough for you to view it.
Liquid Crystal Display (LCD) TVs are a good choice for folks with RVs. LCDs are thin and come in any size you could possibly need. In addition, they are lightweight compared to other types of televisions. Lastly, they are durable enough to handle the jostling that is involved with being on the road. You should avoid other types, such as cathode-ray-tube (CRT - the standard tube-type TV), or Plasma. They are heavier than LCDs, but more significantly, the vibrations and bumping around that is inherent with travel can cause the units not to work.
New TVs that are sold today in the U.S. are required to have a digital tuner built-in. Considering that you will be trying to get signals in various locations, you need the best tuner you can find. An external antenna is a good idea as well, since some campgrounds for RVs are in locales where the signal is weak. An even better option, if you are willing to pay the premiums, is to subscribe to satellite service, and bring your dish with you.
One option that is popular with RV-ers is to get an under-cabinet television. These are units that are mounted to the bottom of your cabinet. They have a small LCD screen that folds down, usually from 6 to 12 inches in size. Most of those units also include a DVD player built right in. This is the most compact solution you can have, since it provides the screen and the DVD player, is lightweight, and small enough to be completely unobtrusive. And because it mounts out of the way, you do not have to setup and take down the unit every time you travel. Additionally, you save counter space. Instead of having a television take up part of your counter tops or table space, they are up out of the way. Look for units where the screen can fold up out of the way so that the space below is still usable, like when you are cooking.
Christy - Under Counter TV info from http://undercountertv.net