If you're expecting "real" Vietnam, walk a few blocks outside of Old Hoi An. Additionally you can go to Cham Island or the neighboring countryside area (aka. Marble Mountains) or perhaps a less-tourist focused city (Danang). However if you just think of Old Hoi An as its own thing (like an Asian Epcot) then it's quite enjoyable. We bumped into a family we had met in Phong Nha and they were saying that it was a pleasant city to be in because of the pedestrian walkways and they didn't have to constantly worry about their children walking around (here sidewalks are sidewalks, as opposed to scooter parking, as in Hanoi). Lots of great buildings and temples, but after a while you kind of wish there was more to the buildings than just a plaque and a bunch of tourists all crowded around (especially annoying with those selfie sticks).
Food in Hoi An
Places I approve of (I'll put pictures of the rest of the food up eventually):
Morning Glory/Mrs. Vu's Market/any of those restaurants-- has great food from all parts of Vietnam (very very tasty and authentic)
Streets/Streets Too which is a pretty good restaurant that takes in orphans and trains them to work in a restaurant-- they force all the local workers to speak English to each other all the time so that they become fluent enough to be able to work at any other restaurant or resort catering to foreigners.
Bale Well isn't bad-- I think we could have sprung for the chicken rice instead (Joe thought that he didn't need to try the Hoi An Chicken Rice since he's already had Singapore's version). The locals ordered it and it looked really good (though they did make a pretty good version of banh xeo). An ok-decent restaurant.
Didn't really find many restaurants in the area where the locals went (and I wasn't sure how good the street food was in terms of cleanliness so I actually didn't have a banh mi off the street or try their deep fried shrimp pancake). The one place I found was a bit out of the way (north of Tran Hung Dao about a block west of Lao Cai) there seemed to be a place where a lot of locals were eating (I think it was close to the ride-a-Vespa-through-Vietnam tour agency).