I haven't read every sentence of the posts above, but it seems to me that none of them deal with what I consider the real issues in choosing an ISP. Here are what I consider real issues:

Do they answer the phone and talk to you, or do you have to deal with several menus, none of which deal with your problem?

Do they put advertisements on your computer? I signed on with AT&T, which told me 'no ads.' Three months later they were putting flashing, gyrating ads on my e-mail program. One day I was composing an e-mail to my nephew about his new daughter and suddenly found myself staring into a stranger's all-but-nude rear end. I found a new ISP.

Do the technical support people talk understandable English? When I call my present ISP, I get to talk to a nice guy named Jason. (I think they're all named Jason.)

Does the Help screen actually help? Or does it have FAQ's such as 'Duh, how do I turn dis computer on?'

If your father has a lot of cables and connections in place, can the new system use the same type of cable? I chose my present ISP (kcnet)because it uses RJ 14, just like the previous ISP.

If I were you, I would have my father talk to friends, etc, and see who's offering customer-friendly service in his city. The difference between $14.99 and 19.99 is unimportant compared to having an ISP with integrity and a good attitude.