If you go by train try Club class. We did this from Stamford CT to both Washington DC and to Boston and really enjoyed the experience, meals, wine and pampering!
Personally, I would avoid using the bus, your fellow travellers can be a bit...ahem....fragrant? It is after all the cheapest way to travel, but in my experience not my favourite! Once did NY to Syracuse this way, never again! Perhaps I am too fastidious?