Well.... I have been searching a bit, using google.
As far as i can see, 4.2.2 is out for "United kingdom", and because you are from Malta, I guess thats the one you want.
Install kies and try to update this way.
If you still want to root and flash custom firmware:
I have searched a bit on how to root a device like your's. Youtube and XDA have tons of information.
Just search for it. The procedure is not tricky: First root, then flash recovery (clockworkmod etc) and finally flash a custom rom.http://forum.xda-developers.com/showthread.php?t=1788625
I really do not know if the procedure in the link will work on you'r device.
Anyway. It is a hint for you to start creating a thread on XDA and start from there, if my post does not refer to you'r device.
Remember. I just did a quick search using google. ;-)
— modified on Jan 28, 2014 3:13:58 PM