That would really depend on what types of wines they like. Wine is very subjective to ones own tastes. First is to decide red or white. Then whether they like light wines or heavier full bodied.
For me I like the heavier full bodied reds with favorate being Zinfandels (not White Zinfandel), Syrah or Petite Syrah. Somewhat lighter reds I enjoy would be Pinot Noir (Burgandy), or Sangiovese (Chianti).
For whites I like Chardonnay or Viogner. I only drink dry wines, never sweet. If you have any idea on what they drink I can recommend a few specific bottles or at least brands that are consistantly good.