To get to Jones the Grocer @ Dempsey, its better to drive. Unless you aren't wearing high heels and dressed up and willing to sweat it out to walk the distance from the busstop in. Parking is also not an easy affair especially on weekdays during lunch time. Alternatively you can take the shuttle bus from orchard mrt in, though the frequency of the bus depends on the number of passengers because the bus only leaves dempsey when its filled.
As for the outlet itself, remember to bring a jacket because it gets quite cold here, especially when it rains. Also do go early to avoid having to wait for your table because people here sit around and enjoy their coffee after meals so you might have to wait for some time. In the meanwhile, you can always go shopping around the dining area, Jones sells pasta, biscuits, rows of sauces and drinks and wines. There's even a cheese room at the back - its really smelly though, so try not to choose a table near it.
As for the food, i really like their apple crumble, its $7.50 if i'm not wrong and its really to die for. In fact, you might not want to share this one with your dining companion.