Carol
Just enjoy the experience, in Hanoi a group of us asked the hotel for a recomendation for some live music and found our selves in a hotel that offered rather more than just live music, but as we were in a group we were OK, in Ho Chi Minh City I'd recommend the Rex Hotel roofbar, a group of us went for food and drink and spent the evening watching the city below (watching people crossing the busy roads and experiencing it yourself is great), in Hoi an a massage is a must, we did have rain so take a waterproof coat but temperatures were not too low. I also went for a ride on the back of a moped around Ho Chi Minh City, having seen the traffic I wanted to experience this, although this is an activity that the tour manager and local guide will not recommend.
Hope you have a wonderful time
Tim