You have changed the SSID and set the encryption which is good. Take it a step further and stop the SSID from broadcasting which will stop anyone from knowing that you have a wireless network setup. It should be a simple matter of choosing enable/disable from the online setup.
You did not say if you are using a wireless card or built in one in the laptop. If its a card then on it you should see MAC and then a mix of #'s and letters. With it you can enable Mac filtering using the interface which will only allow that card to interact with the router wirelessly. To test ask a friend with a laptop to try and use your network and if you did it correctly they will not even be able to find it in a search.
As for the firewall it putting a wall before the one on your computer, good but not something worry about. Just use D-link online support for help in setting it up.
Sorry could not give exact info as I have not use D-Link but the info is general for all of the big makers of routers as they all offer the same things now. Someone else may be able to give exact info.
I have just installed the DI-624 to set up my wireless network at home. I followed the instructions, changed the SSID, changed the admin password, and enabled WEP 128bit encryption with a random key. (I was going to use WPA, but my laptop does not accept WPA, so I am using WEP.) My landline computer has Internet Security with firewall enabled and Internet virus scan.
First, is there an easy way to test to see if I have adequately protected my wireless network so that no one can use my network or gain access to my home computer?
Second, I haven't figured out how to properly set up the firewall on the DI-624 itself. Is this necessary or is having the firewall on my computer sufficient.
I'm a newbie at the whole wireless realm, so any help would be greatly appreciated.

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