Don't know about WDW, but since I'm on the Magic right now, here's how it works.
They have an internet cafe with access and you are billed either 75 cents a minute or you can splurge on the Unlimited Plan at $89.99. Basically, if you plan on spending more than 17 minutes a day, its good to go with the Unlimited Plan. Also, the connection isn't as fast as the DSL I have at home, so it may just take longer than you think because of the connection. The other thing I noticed is that the clocks on the computers are disabled, so you can watch how long you're on.
As for checking his e-mail, he'll need to be able to access his e-mail from the internet. I have a yahoo mail account, that I use, but for work, I have a special URL I can go to and check my work e-mail.
If you have any more questions, let me know, I'll be checking in again tomorrow.