none of your devices working wireless still???
try log into 192.168.1.1 page, and go to interface setup, wireless, set channel as 11, disable WPS, change the SSID to a new one, check the security key. save and reboot.
try connect the new SSID and put in the security key, see what happens.

Okay, I've done what you've told, still same problem, and I did disable autentication type to ease the connection, still nothing ....

I think I might have a clue ... with my PCs, PS3 and Voice IP, I had to enter the ISP username and password to connect to the internet even via my Router. Might it be because When my WIFI is working, my 2 mobile devices doesnt have the option to select a user and password for the broadband connection ?? My devices connects normally to the Router, but arent able to connect to the ISP internet connection ?

Normally the ISP username and password are put into the modem, thus there is no need to do broadband connection on any of your wired and wireless devices at all. so i suppose you may need to do the quick start again, put in correct VPI/VCI, connection type and ISP username password.