Nothing is really broke here but I'm finding today's new owners to be either un-understanding or even incredulous about this old OS. There's a lot in this old beast. Sometimes it's buried, sometimes you have to tweak.
Win7 home premium 64 bit
MS Office 2010
I started using Outlook as an email client (RIP Eudora) and don't remember this dialogue box before that.
My PC connects to my DSL modem and wifi netork on boot up.
I can't begin to imagine where the setting would be to have something look for a dialup connection when the network is always available??!