Stop sideway movement of menu revealed from top On my Galaxy S3, when I slide my finger from the top edge of the screen down, a sort of quick menu is revealed to switch WiFi, GPS, sound...

When it is revealed, the animation goes from top to bottom but also slides sideways. I would like to stop this sideways animation, but I don't even know how this menu is called to Google it and I found no setting for it so far.
I believe you are talking about the notification drawer, and the top row of icons that toggle functionality like wifi, GPS etc.

There appears to be no way to customize what appears in the top row when you are on Samsung's stock software/ROM. You'll have to switch to a ROM like CM9 for that.