Are you saying that you are using dial-up when you have ADSL available??
Either way however, I think you can plug your wireless router in anywhere - well at least there's no harm in trying it. My ADSL/broadband wireless router is connected into a BT wall socket in my 'study' (a bedroom) which I wired in myself as an extension from a pre-installed socket in the main bedroom which is itself an extension from the main incoming BT box in the lounge.
And no, it doesn't cut anything else out.