The problem is modern wifi routers do not generally support wep security. Its very unsafe and easily broken. Try changing the security box to wpa or wpa2 if thats an option. If you really need to use it wirelessly you might be better served with a cardbus wifi g/n card or one of those ethernet to wifi bridges or just plain old ethernet. I doubt you would really want to use the original airport these days anyway. Its wifi b which is very slow. If you do want to use the original airport the easiest thing to do is probably buy an old used wifi router, set it up with wep security and turn it off when your not using it so people cant hack in.
Not janky at all. I have a dead spot in my bedroom, so I feed the internet signal via some powerline units into my room and thence to an old AEBS. That one is set up for my older Macs.