I am looking for a dvd changer (that holds 3 or more dvds) that skips all the menu (previews) of the DVDs and directly plays the first dvd movies and continue to do the same with start of the next dvd movie, and so on. For example, if I insert three dvds in it and press play once, I will be able to watch all movies continuously to the end of the last dvd movie without lifting a finger to press another button.

I'm not sure such a player exists. The only way I can get that to happen is to make backup DVD+R discs of the Movie Only (strip out all the menus) and put the player on a Play All loop.

foryoinfo

According to the instruction manual the
Onkyo DV-CP704 6 disk changer has a 'Chain Mode'
that will do what you want. I have been searching
for this feature also.

Cut & paste from instruction manual at onkyousa com
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With the Chain mode function, you can play all discs, all
DVD-Video discs, or all audio CDs and MP3/WMA
discs consecutively as if they were one big disc.

Note:
• JPEG files are skipped during Chain mode playback.
• With the DVD and All Chain modes, DVD-Video
- menus are ignored and titles are played automatically.
This may not work with some discs.
• You can’t use the repeat functions with Chain mode.
• You can use the Random function with Chain mode.
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As the note says it may not work with some discs.
If you took prospect60's suggestion to burn just the movie to
a DVD+R disc you would not have a problem with any that
didn't work correctly.

Hope this helps

John