We've stayed at POP a few times. You will enjoy it. One time we were there, we were eligible for RAC (I think it was United), but they were having computer troubles and couldn't print our boarding passes. I went to POP's registration desk and explained the problem and they printed our boarding passes with no problem.
That being said, you really need to check in with SW at the 24 hour mark so you have a better chance of getting A boarding passes. If you have a web enabled cell phone or a Blackberry (or similar mobile device), you can check in for your flight from anywhere. We were at Epcot 24 hours before our SW flight in April and I checked in for our flight while we were watching street performers in the UK. It was beautiful. Here is some helpful information from SW's website:
Southwest Airlines Wireless Access puts you closer to the travel information you need while you are on the road and away from your computer. You can access several key southwest.com features via your web-enabled mobile device.
Web-enabled Mobile Devices (Help/FAQ)
Available at mobile.southwest.com
Flight Checkin - Check in now and print your boarding pass at the kiosk later!
Cancel Boarding Passes
Southwest Airlines Contact Information
Terms and Conditions
Privacy Policy
Finally, I have heard that people have had good luck going to guest services at any resort or park and they've been able to do computer check in.