wifi and security

The other evening I was in a chat room. One of the other chatters was out of town and without Internet access, so he was using someone's unsecured wifi network. That one wasn't fast enough for him, so he hacked his way into a better network that only had WEP for security. It only took him a few minutes to do so.

Initially he only wanted Internet access, but while he was inside, the network's owner sat down and entered her Facebook user name and password which was also her AOL user name and password. He posted this information into chat for all us to see so we could mess with her if we wanted. I thought this was incredibly uncool (not to mention illegal).

As I only WEP for security too, I asked what I needed to do to protect myself from someone like him. He humored me with an answer. Upgrade to WPA2 and choose a really long, random password. This wouldn't be hack-proof, but most hackers would move on to easier targets. As I do my banking online, I'm thinking I need to take his advice.

We have four computers in my household. I know that my MacBook Pro can do WPA2, but I'm not at all sure about any of the other computers. They are:

Macintosh Dual 1.25 GHz PowerPC G4, 2 MB L3 cache processor, 1.5 GB DDR SDRAM, Mac OS 10.4.11

a cobbled together PC that my husband's gamer friend sold to him which isn't currently set up so I can't get its specs

a positively ancient Macintosh iBook G3, possibly the first model ever sold

The router is a relatively new D-Link.

Here's what I know/hope/guess:

I hope the G4 is WPA2 compatible, but I know its Airport card isn't. Possibly I could steal the wifi dongle off the PC. That might be WPA2 compatible. If necessary I can purchase a new wifi card for the G4.

I don't imagine the iBook G3 will work with WPA2 under any circumstances.

The PC is an unknown factor for now.

These are my "d'oh type" questions:

When I first set up the router, I used the PC to do so. Can I use my MacBook to set up the router or do I need to hook the PC back up again?

If I have to use the PC to set up the router, I switch it to WPA2 and then find out that the PC isn't WPA2 compatible, how on earth would I switch back? (I'm guessing that would be problematic.)

What are the rules for WPA2 passwords?

Is there anything else I should do to make myself more secure like some kind of firewall? Does the Mac OS have a good built-in firewall that I can activate? (I have OS 10.5.8 on the MacBook Pro and Snow Leopard that I can install.)

If you read this far, then thank you very much. I know this was very long. Any and all advice is appreciated.

FWIW, the girl whose Facebook got compromised, I e-mailed one of her friends (because the hacker would've seen if I'd e-mailed her directly) and told them to tell her what had happened so she could change her password and make her network more secure.

WEP is a laughable security measure. It is unbelievably easy to crack. WPA2 is pretty secure. The attacks are bruteforce to guess the password. This is why if you have a long strong password it is quite difficult to hack. If it is a common name, dictionary word, etc one can crack it. Once you make it a sentence with random characters, punctuation and numbers these types of attacks won't work in our current lifetime with our current computers. (Unless you have your own 75k botnet) Check out how long it takes just to find Mercedes.
YouTube - crack wpa2 easily with crack-wpa.fr

Anyway I do have a G4 mac mini and it does connect to WPA2.

Which dlink? Most modern routers use a web based interface so anything would work. If it is a install file you may need run it on the PC. For example my netgear can be setup by any OS including linux.

The longer and more random and more charcters, capitalization, and numbers you use the better off you are.

For the PC run an all in one like Symantec - so you have firewall, malware, virus protection. For the macs if you are paranoid turn on a firewall. I have mine on but I am paranoid.

The way facebook got hacked is probably packet sniffing. So unless someone cracks your wpa2 network you don't have to worry much. If someone is on your network they can packet sniff and anyting you send over the web can be sniffed. If you want there are ways to sign into facebook like you would for your bank using SSL like a firefox add on.
facebook secure login - Google Search
This also goes to show - if you are on an open network - don't log into anything that isn't https/SSL.