How to make a movie with a Nex7 ? No idea why I fail. Help wanted.

Finally tried making a movie of 30 seconds of my dog.

All I want is: shoot movie, cut out he best part, save as MP4 and put it on YouTube.

Settings on Nex7:  MP4, VGA, sound OFF.

No idea what AVCHD means (looks like a Sony special format) so after trying and not able to playback I gave up on that format.

The Sony manual of the Nex 7 is of no help to me.

So I shoot a movie. Connect the Nex to my Vista operated laptop

Look around on the *removable disk* / MP_ROOT / 100ANV01

(no simple maps like FOTOA or MOVIES but for me incomprehensible names like MP_ROOT)

There I find the movie called

MAH09725    MPeg-4 movie     57.678 KB

AND

MAH09725    THM file             7 KB

Cannot find anywhere what the THM file is and what it is for.

I copy them both to my hard disk

Click on the Mpeg file and choose *open with*

options on my PC  (1) VLC media player  and (2) Quicktime

both give a horrible rendition of the movie while playback on my Nex is OK.

Glad I like photography, but I sure tried to make a movie. No succes whatsoever.

Is there help somewhere?

Please note I allready know how to switch OFF the Movie button ;-))