You question doesn't make it clear if your problem is entirely local (two machines connected by your home router, and you can't connect from A to B) or whether it is entirely remote (attempting ssh connection across the internet through your ISP.) For the latter case, it is possible, if you're sure you've done all the right things, that your upstream provider (ISP) is blocking connections to the normal ssh port (22) on your system. If this is what is happening, you might can try running sshd on a different port than the default one, but you'll of course have to give this new port number in your ssh connect attempt from the other side.
At any rate, please clarify where the problem is. =)