I chose the "new series but prefer the old" but, dammit, I came to them both at the same time! Never watched Who as a kid, but watched semi-regularly when the ABC started repeating all the episodes they could (there was problems with the Daleks, apparently) at 6pm weekdays. Started watching far more regularly (with more intent, given that the other people in the house didn't want to watch the show and it was on over dinner) when I started to hear about the new series from my flist. So technically I think I came to it through the new series, but I prefer the old.

Sometimes these things aren't that clear-cut, dammit!