Well some routers incorporate a VoIP facility with the ability to loop through a fixed line, so on one analogue phone, either wired and wireless, you can receive and make VoIP and/or fixed line calls. Sorted, meeting your exact requirements.
True, I used to use a FritzBox 7140 but it won't handle Gigabit ethernet. Besides, analogue phones are somewhat limiting these days.
But why would you want to have access to a fixed line? Calls via VoIP are much cheaper and you can port in your existing landline number, but of course you need a landline to drive the router, unless with Virgin.
The landline and broadband (FTTC) are with Sky (we no longer have Sky TV but used the money we used to spend on that to pay for the FTTC upgrade). Virgin isn't available in this area, if it was available we might consider it, but it's unlikely here anyway as we live in a 3-story block of council flats and the way the building is constructed means getting additional cabling or fibre into the place is a non-starter
We want to hang on to the landline anyway, as the tariff we have gives unlimited calls to landlines and mobiles so the VoIP lines are mainly used for incoming calls.