This.
If possible post your .conf file (after censoring out anything that's not supposed to be public ;] )
What error does the browser throw at you when you try to connect? (DNS_PROBE_NOT_FINISHED? ERR_NO_CONNECTION?).
What does the OpenVPN log contain (those are usually added to the syslog, " grep VPN /var/log/syslog " this should print out some stuff)
Have you enabled ipforwarding? ( run " sysctl net.ipv4.ip_forward " from the terminal, the proper value should be 1 )
Regarding IPTABLES - did you set up SNAT or MASQUERADE ?
Those are some things of the top of my head without any proper debugging info, but it should get you going.