I would say that it takes 5 minutes to get from the townhome to Disney property, which is different from actual time to the parks. Animal Kingdom is the closest, Epcot and HS about the same, MK the farthest. Traffic lights and time of day probably play a factor when people are stating how long it took to get to a specific park. I'd probably say 10 minutes to pulling into a parking spot at AK, maybe 5-10 minutes longer to the others, again depending on various factors.
But, I'm also certain that WH is closer to the parks then some of the onsite resorts. Assuming a rental car (which you would definitely want), the drive is very easy. We went back to the townhome everyday for a mid-day break and swim. I kind of feel like I've been spoiled. We've had 3 trips now offsite, the last 2 in a 3 br/3 bath home with it's own little pool and a washer and dryer. I can't even imagine doing a 10 day trip in a hotel room.
If money wasn't an issue I'd love to rent points for a onsite DVC 2 bedroom. But since it would cost at least double, maybe more, we'll stick with whats working for us.
I'm happy to answer any other questions.