Two great drving roads I can think of in MA:Got a couple of great roads in Massachusetts... no wait, there arent any here
1. The Mohawk Trail (Rt 2) between Deerfield and North Adams. RT 2 is pretty damned good the whole way, but this is the best bit. Mountain streams, curves, picturesque little towns, no traffic (except in the Fall).
2. RT 116 from Conway to Adams. You can pick up 116 in Amherst (after enjoying a fine brew at the Moan and Dove in South Amherst... just one, that's all I'm saying) and follow it all the way to Williamstown. This is like a back-roads version of the Mohawk trail. The bit through Ashfield, MA is particularly cool.
Yes, I grew up in Western MA.