Block links on navigation menu

Hi Guys,

on my website ( http://www.saleolio.com ) I’d like to block the links of the navigation menu you can see going with the pointer on “PRODOTTI”

Basically now you can click on all the options that the navigation manu gives you but i’d like to allow people just to click on the most detailed page so that the only path possible is for example:
“PRODOTTTI>PRODOTTI SALATI>NOSTRI PRODOTTI SALATI or PRODOTTI SALATI DEI NOSTRI PARTNER and make possible just to click on the last two.

It’s quite confused but i couldn’t explain better… Let me know if it makes sense…

Thanks!

T