How can I rip my DVD to play them on my TV? I would like to rip a DVD on to Mac then onto a multimedia device to play them on my TV set.

Is there a software that will help me to do so?
You can use HandBrake. 


  HandBrake is an open-source, GPL-licensed, multiplatform, multithreaded video transcoder, available for MacOS X, Linux and Windows.


There are a lot of built-in preset  you can chose from to rip your DVD to a format you'll be able to play on your multimedia device.