A free programfor using to convert video file from different format to iPad format on Windows is: Free iPad Video Converter The principal characteristics are:
Input format
HD
Video, AVI, FLV, SWF, DV AVI, MP4, WMV, 3GP, 3G2, MOV, QT, DVD, VOB,
MPEG-1, 2, 4, MOD, MPG, DAT, RM, RMVB, ASF, H.263, H.264, MKV and TS
Output format
M4V, MP4 and MOV
Easy to use
The convertion time is in the range from 20 min to 4 hours (3,30 hours
is the time necessary for convert a video of 1,5 GByte on my NetPC
eMachines, CPU N450 at 1,66 MHz and 1GByte of RAM).