Re-reading all your post carefully. I guess, the aspect ratio of the original DVD should be 2.35:1, and when converting, our program will output it as 1.78:1, so there will be huge black bar both on the top and bottom. Now, please follow the steps below to try again, and then tell me the result.
1) Download the latest version 2.0.4 of Ideal DVD to avi conerter from
http://www.idealdvdcopy.com/download/IdealDVD2AVI204.exe and just install it. Note, you needn't uninstall the existed version. Just close the current version, then double click the new setup file to install. This version added "Crop to 2.35:1" function.
2)Click "Options"->"Configure"->"Profile", choose "Crop to 2.35:1" as following.
3)Rip the troubled DVD again, and stop it after 1 minute.
4)Playback the ripped file on your 32 inch and 42 inch TV and tell me if it's better this time.