Oaks and tannins ruin a good curry. Stay away from anything aged in Oak barrels and stay away from Reds with high tannin content.
A bottle of Riesling, or Sauvignon Blanc, Chardonnay or Pinot Blanc will all work with almost any spicy dish.
Viognier goes particularly well with Thai food. The herbal notes of the voigner grape add complexity.
Red Wine: Low tannin wines such as Chianti and Merlot
If you are looking to drink a red wine, then a low tannin Chianti or Merlot are fantastic with rich earthy dishes such as the wonderful curries of the Kashmir.
An additional benefit of wine with spicy food is that the alcohol washes the chilli into the toungue making your spicy food slightly more intense than before.