Hi Boris,
You are in the right way now! Just follow what DaveB said and change your httpport parameter in your config.tcl to
httpport 80
Also be sure your ip address is correct with you configured network interface
set address 192.168.1.3
or just try:
set address 0.0.0.0
Dont forget -b flag. You can start your server as root but just check if it will run under your service0 userid (just type ps auwwx |grep nsd). Also check you are not running other service at port 80, ok?
Why not try daemontools? It is very usefull to keep your service alive.