AFAIK, the ISP software is only relevant to the ISP supplied modem. An ADSL modem/router makes its own arrangements. Once connected, there's no noticeable dialling effect. Very occasionally, the router may lose connection, but it should normally re-connect without any user input.
It's some time time since I used the ISP supplied modem. Mine was connected to the PC by a USB cable, which also powered the modem. So when the PC was shut down, it also cut the power to the modem, and disconnected the broadband connection. On power up, the modem had to re-establish the ADSL 'handshake'. The Netgear etc, has its own independent PSU, so this isn't an issue.
You'll also need an ADSL Filter for each telephone in the house. (Without them, you'll hear noise on the phone). Don't be tempted by the cheapos, I've heard many horror stories. We're using three Speedtouch UK413s, and they're excellent.
Edited to add:-
I would hope the DG834GT shown in the link would fit the bill. It's a later version of the Netgear (DG834G) we've used for some time, without complaints.