Thanks John.
The following rules seem to work for me now.
sudo /usr/sbin/iptables -F
sudo /usr/sbin/iptables -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
sudo /usr/sbin/iptables -A INPUT -p icmp -j ACCEPT
sudo /usr/sbin/iptables -A INPUT -i lo -j ACCEPT
sudo /usr/sbin/iptables -A INPUT -p tcp --dport 22 -j ACCEPT
sudo /usr/sbin/iptables -A INPUT -p tcp --dport 80 -j ACCEPT
sudo /usr/sbin/iptables -A INPUT -j REJECT --reject-with icmp-admin-prohibited
are there any problems with my setting above?
Thanks