Can't help on the train trip as I've never taken it, although I live nearby and have seen the train at the platform in Vevey station. Just can't understand how it could take 1.5 hours from Lutry to Vevey - it's a 10 minute train ride along the lake. Even though the train des vignes leaves the mainline track and goes up into the vineyards to Chexbres, it can't add much to the journey. I think there's something fishy about the timetable. And I doubt SBB does a service which stops at different wine producers to allow some tasting. But I can recommend one place midway between Vevey and Lutry to do some wine tasting:
http://www.testuz.ch/treytorrens.asp?l=1