Penfold's Grange if you're buying, Penfold's Bin 28 if I am. If we're on a budget, there's an empty bottle of St Martin's Road Shiraz in the kitchen and another few bottles in the wine fridge.
Tesco do a really cheap but really nice pinot grigio.....its called Simply Pinot Grigio, I drink far too many bottles of that a week, Tesco finest chablis is also really good. As for red, Wolf Blass yellow label Cabernet sauvignon is fab.
Brut champagne - preferably Bollinger or Ayala. But on a more sensible level for everyday drinking, Montepulciano or Montalcino. For a special occasion, a decent Beaune.