Scroll pages smothly

That is not language related. Not sure what are you talking about just get rid of second jquery ref

Sorry but I don't know what you mean
I use a plugin "videobox" to show youtube videos, but this plugin isn't repeated.
Could you show more clearly the problem?.
Thank you very much.
Best regards,
Angel

Turn off jquery reference added by videobox , you have it form template. Two refs on same page are creating problem.

Deleted recomended jquery, and all continuing without smothly scroll,
Regards,
Angel

Wait maybe we don't understand each other, do you thing on page scrolling animation on our demo when you click on menu item - that works if all content is on same page (template name is "one page"). All your links are external so they work like on common site.