I have a few of these deployed around one of our offices. I've never had an issue using it with my Powerbook, but there are a couple of things you need to know. Firstly, they are not a router, they're an access point. That means that they won't be able to handle the task of sharing your internet connection among multiple computers. If you use this access point, you'll have to have another device to share your connection. I'm assuming that is what you want to do, since you're referring to it as a router.
As for the security settings, it supports 128bit WEP encryption, which is no different than most 802.11b devices. The configuration process is simple enough, I had 2 of them up and running in 10 minutes. If it would help you, I can take some screenshots of the config screens when I get to work.
Just remember that WEP isn't secure, and coupling it with mac address filtering and non-broadcast ssid's doesn't help much. If you really want to take the security seriously, consider getting a router that supports WPA-PSK.