Heh... well... don't be so quick to say that it's "secure" just because you put a password on it. But you can make it rather inconvenient for someone to intercept your data, for sure.
Plus someone is much less likely to **** with your wifi at home, as opposed to ASU's network. Here's the breakdown:
1) No security. This is what ASU's public wifi network has. It's like this so that anyone can log into it.
2) WEP. This is at most an inconvenience for someone who knows what they're doing. You can get through it in about 15 minutes. But it'll keep out the ultra-noobs.
3) WPA. Much better. Will take about a month of packet sniffing to crack the key, so you can count on it being secure. I mean, I doubt you're doing anything so important that a hacker would want to devote that kind of time into, yes?
But seriously, the number one thing that you want to do for your home wifi router is change the default username and password. Dear god, change the default password.
If you don't, it's so easy to just drive up in front of your house, plug in the default username and password, log into your router, and upload it bad firmware, bricking the router, and just drive away. Too bad, go buy a new router, good day sir.
Not that I would do that...