Not trying to confuse further, but I think the 'network' and 'broadcast' entries can be left out entirely as the netmask line already defines these values. I never add these lines to my /etc/network/interfaces and it works just fine. Makes the file look a little neater too.
You'll also need to set a DNS server if you ever want to run updates on your Pi or simply access the Interwebs from it.
The dns address goes in /etc/resolv.conf
Example /etc/resolv.conf
search .
nameserver 192.168.0.1
(Assuming that your dns server is also hosted on your gateway)