I've delved into this simply from a personal interest level. As indicated previously there are some decent tutorials using the Backtrack 4/5 iso image which you boot into. That's your best bet. Just a few tips
1) Windows drivers generally are pretty bad at allowing you to go into the required promiscuous mode on the wifi card, this is why Linux is generally recommended
2) Admittedly the backtrack tutorials are somewhat... lacking at times if you're not 100% understanding of what each step does and how it works.
3) The tutorials assume you know a lot. Spend the time to learn what each tool does and what it's doing at each step. Really this is the fun part!
Start with a WEP system. If you're brave set your AP into WEP mode and experiment on it with backtrack. Once you figure out the commands you'll see how easy it is to hack. Going to WPA/WPA2 is different. This really depends on either a rainbow table or a gigantic dictionary attack. You could as a test make your dictionary have your WPA/WPA2 key in there so you know the process works. Again this is a lot of fun to learn how the tools work and such.
Now some basic wireless security. DO NOT ...
1) Use WEP. Just make it open or just put your password in neon lights in your window. It literally takes more time to boot into Backtrack that it does to inject the 50k packets and crack your WEP key. It's actually fun to watch!
2) Use a short WPA/WPA2 key. Short WPA/WPA2 keys are vulnerable as well. Use at least 15-20 characters.
3) Disable SSID broadcast. This is the equivalent of putting a cardboard cutout of a cop inside your house. It doesn't deter anyone.
4) MAC filtering. Again entirely useless since MAC spoofing is absolutely trivial
5) Use the default SSID. Even if you make your WPA key long, having the default SSID is a bad idea. Rainbow tables exist that make cracking such AP's trivial.
Anyways good luck and have fun learning.