I'm not an avid Friends watcher but I tune into the odd episode if it's on.
Three lovely ladies, who would you have as your wife? I'd say judge your decision on what they looked like then, not so much now (although Monica ain't too bad these days!)
Personally, I think Monica was the most natural looking. In the first few series, she's HOT! Lovely dark hair, fair complexion, nice figure and she can cook! Result!