Where in Queenstown are you staying? The traffic between the actual town and its suburbs can be pretty heavy at certain times of the day (generally when trying to get to and from the ski fields, and to and from work). Most tourists will be based in the actual town, where most hotels are. If that's where you are, it'll be a lot easier sticking to the restaurants there, thus avoiding further traffic woes.
Totally depends what food you like, but some of my favourites are, in no particular order: Bella Cucina (Italian, with more than just pizza and pasta), Margos (Mexican), The Taj (Indian), Tatsumi (upscale Japanese), Kappa (more casual Japanese), Rātā and Botswana Butchery (upscale NZ/international), Blue Kanu (NZ/Pacific/Asian fusion), Caribe Latin kitchen (essentially South American street food, but you can eat it there too), The Cow (pizza/pasta in a hidden away old stone building -- not authentically Italian, but a local institution and good for families), Eichardt's Bar (tapas). There are plenty of other places I haven't been to that are also well-regarded. A good lunch/coffee place is Bespoke Kitchen, up the hill towards the gondola, upstairs from the medical centre.
Heaps of bars in town, varying from basic to fancy.
Arrowtown, if you have a car, is definitely worth a visit, and there are some great places to eat there too: Aosta (Italian, spendy), and Little Aosta (at the back of Aosta -- more casual version), La Rumbla (tapas), Mantra (Indian).
There are some nice breweries outside town -- a couple that spring to mind include Canyon Brewery (at Arthurs Point, above the Shotover River -- a good stop on the way back from Coronet Peak), Cargo at Gantleys (also Arthurs Point), and Altitude Brewing (lakeside, by the Frankton Marina, and on the way back from the Remarkables).
Many of the wineries also have great restaurants, most notably Amisfield. Gibbston Valley is where most of the local vineyards are, and a bit further afield is Bannockburn (45 mins drive away), Most of them do tastings, I'm pretty sure.
Skiing is basically Coronet Peak and the Remarkables, unless you're doing heli or backcountry. Coronet Peak tends to be the locals' mountain as the road is fully sealed to the top, which makes it easier to get a few laps in before work. So the carparks fill up early, but empty out early too. It's lower so the snow quality can vary a lot. When the snow is plentiful and good, it's a really fun mountain to ski, with something for everyone (except a terrain park). When it's not, at least getting away again is a bit easier. Remarkables is a bit further from town, and the road can be confronting for some drivers not used to it. A 4wd rental would definitely be more useful here. It has a lot of big-mountain, hike-to terrain, and a good terrain park. Also plenty of intermediate skiing with 2 fast chairlifts (out of 4), and a good learners area. Thankfully school holidays have ended, which should have relieved the traffic/parking pressure it was experiencing a few weeks ago.
Cardrona is about an hour's drive from Queenstown, Treble Cone about an hour and a half.