To the OP, you have 2 choices. 1. Convert your movies with a free program such as handbrake and then sync them to your ipad. 2. Purchase an app such as AVPlayer HD or similar and just copy your files onto the iPad and these apps will be able to play them.
1. Handbrake does a very good job of converting DVD's to the proper format for the ipad (there is an ipad preset you click on). Once the DVD has been converted then you will go into iTunes, select the movie/video tab on the left hand side and then go to file (on the top tool bar) and then import. Locate the file and double click on it and iTunes will import it to the library. Now hook up your ipad to the computer, click on your ipad on the left hand side and then you will see a new area open in the center area of your screen with tabs at the top of it. Click the movie/video tab located on the center top of your screen, make sure there is a check box next to the video file you just imported and then click sync down at the bottom of the right side corner and let it do its thing.
2. I got tired of spending time converting so I just purchased AVPlayer HD. There are also other good video player apps but I had heard good things about this and so far it has been great. So with this app you will need to have the video files somewhere on your computer. Connect your ipad to the computer, iTunes should open up and once it does click on your ipad located on the left hand side. Now at the center of your screen you should see tabs like apps, music, pictures, video and so on. Click on the apps tab, scroll down to the very bottom and you should see another section down there and AVPlayer HD should be listed. Click on it and you should see a little box area towards the right of it appear. Simply drag and drop the video file into this section and it will copy it over. That's it, very simple and easy to use. I believe you can also do a wireless transfer of the video file but I have not messed with it.