If you want drop-dead simple, no need to know any settings or do any work/thinking, my favorite option is Media Studio for Blackberry. Not free, but pretty much click/click, done.
Choose your movie (from file or directly from DVD) choose your Blackberry model, there are a few options for optimizing sound or video quality, etc., and go.
If you connect your BB it will complete the conversion and then copy the file to your SD card. DVD and video to Blackberry - only two clicks needed
They have what looks like a new/recent 2.0 update available.
There are other (free and paid) options if you're willing to do a little searching/reading in this forum.