NETBIOS is ancient...disabling NETBIOS altogether on networks(provided you are sure you want to do this) can be a good thing for both your network and your windows workstations.
For those of you using the default node-type, you will basically eliminate all netbios broadcasts on your network,and your workstations will ONLY use DNS for resolution, instead of DNS then WINS then NBT broadcasts.
Disadvantage is that you can no longer use tools like nbtstat to query machines on your network for their hostname (shouldn't you be using DDNS?) and connectivity using some 'short names' may be lost...but you should be using FQDNs whenever/wherever possible.
DHCP Option 43, value is "01:04:00:00:00:02"
The line in your ISC dhcpd config should be:
option vendor-encapsulated-options 01:04:00:00:00:02;