Is your router IP address 192.168.0.1 ?? You must assign static IP addresses in the same subnet as your router is working. So generally speaking, the 1st 3 digits of your static IP address must match the router's IP address.
2nd, you should assign static IP addresses outside of the range your router uses for DHCP assignments. Going though your router's configuration info should allow you to discover what range the router is using for DHCP. If the range covers everything from 2 through 254, then change its configuration so you have some room for assigning static IP addresses.
NOTE: Some routers will allow you to continue to use DHCP and will make the Port Forwarding follow your system's MAC address (Media Access Control device; aka your ethernet address or WiFi address). If your router supports this, it would eliminate the need to use static IP addresses.
3rd, it is possible that your Mac did not pick up DNS server addresses even in DHCP w/manual IP address. You could try configuring your own DNS server addresses via System Preferences -> Network -> Advanced -> DNS. You could just plug in your ISP's DNS servers, or you could even use the <http://OpenDNS.org> DNS servers.
NOTE: If you are going to get into Port Forwarding so you can access your systems across the internet, you should look into getting a free <http://no-ip.com> or <http://dyndns.org> dynamic DNS name and running a dynamic DNS updater on one of your home systems. This will make it easier to find your systems when away from home.
