As an analogy, having unsecured wireless and dealing with intruders is kind of like keeping your door unlocked, hanging up a sign around your block telling people about that, and then waiting inside with a loaded shotgun. Can be fun, but most people don't take your side on this..
WPA with a long randomized key should be able to secure your wireless network adequately. If it doesn't, then I'm sure we'd love to hear about how it got cracked, and why.
If you can't get WPA working for some reason, you could also get some help here.