I use Talk Talk with a Netgear DGND 4000; a very good router. I would guess that the best of the ones you have is the Netgear DG 834PN . As an alternative, or addition, you could consider a Homehub wi fi extender _ this creates a wi fi spot upstairs via the mains.
Although some do not recommend it, I have my router plugged in upstairs on a 25 m phone extension. I get just as good a download as when it is plugged into the test socket, and get a better wi fi range.