Download handbrake
select a video source, even a folder source can be added,
On the right hand side there is a Preset Coulmn
there under devices seled Android Mid or High
as name suggest it means medium quality or high quality meaning smaller and larger file size respectively...
also for streaming options there is an app called Plex media Server for Win/mac/linux [which i use]
http://www.plexapp.com/
and a $4.99 app in android market,
https://market.android.com/details?id=com.plexapp.android&hl=en
if u are in home network u can use it to stream of your Desktop[which will act as server] and stream it to you while converting your media on the fly !...
if its a desktop thats used freqiuently see to it its atleast core2duo @ 2.4 ghz cuase it will load the CPU whenever you stream!
but if u really want media on devices i say handbrake is way to go!
also if you gonna use windows version, enable query generator
this will show a query generator tab which u can use to generate query and use it in the bulk conversion app
check these links for more info on handbrake
bulk Conversion -
HandBrake Batch Encoder Simplifies Multiple Video Conversions
Rippping your owned DVDs -
How to Rip DVDs with Handbrake
EDIT: i use Ubuntu Linux and i just noticed that the windows version dont have the android mid/high presets.... u can try it with iphone 4 or ipod touch and try