I was thikning more something like this...
iptables -I INPUT -p tcp -j DROP
iptables -I INPUT -p udp -j DROP
iptables -I INPUT -p icmp -j DROP
iptables -I INPUT -p tcp --dport 80 -j ACCEPT
iptables -I INPUT -p tcp --dport 53 -j ACCEPT
but actually that won't work either!!
the syntax for what you are rtying to do is all wrong. I assume that you are trying to, bascially you want to be able to browse the web, but you want to protect your computer from outside attack, and you'd want to stop your computer making connections to other people...
this is what your conf file should look like.
### IP table conf file ###
# Set default policies (drop all connections)
:INPUT DROP [1:44]
:FORWARD DROP [0:0]
:OUTPUT ACCEPT [27040:2493902]
#allow web traffic requests out
-A OUTPUT -p tcp --dport 80 -j ACCEPT
#allow DNS out
-A OUTPUT -p tcp --dport 53 -j ACCEPT