As is well-known, if you want to add some music or videos onto your Apple portable devices, you have to do that with iTunes; if you can not upload the files to iTunes, you can not sync them to your iPad, iPod or iPhone. So want to add videos to iPad, please add videos to iTunes first. You know the iTunes only supports few video format, like MPEG-4 or H.264. For most of your videos, you have to convert them to iTunes format.
The guide below will show you how to add videos to iTunes when they are not supported by iPad. What you need is the most professionaliPad Video Converter + DVD to iPad Converter Suite, which can convert all kinds of videos, including DVD, AVI, WMV, MKV, RM, RMVB, DivX, ASF, etc. to iTunes supported format. After converting, you can add video into iTunes smoothly.
TIPS: For Mac users, theiPad Converter for macwill help you add movies to iTunes on Mac.

Guide: How to Add Videos to iTunes

Step 1. Run Program
Run the iPad Converters and select the icon "Video to iPad" as shown below.
Step 2. Output Settings
import the objective videos into the program by clicking the "Open file" button. Then from the "Profile" drop-down list select the proper output format and set the output path as you like.
Step 3. Start Conversion
Press the big "Convert" button to start converting videos to iTunes format. You will see the conversion finished very soon, needing just a few minutes. After that, open the output folder and transfer the converted videos to iTunes. That's it! Then you can connect your iPad, iPod and so on to sync the videos to your portable device. Now you have completed the whole progress of adding videos to iTunes for iPad (iPod or iPhone)! Besides, you can alsoAVI to iPad,DVD to iPad 2 Converteretc. in the same way.