Personally, I enjoy complimenting people, regardless of age/gender, though they would obviously be different in content & delivery. I used to be far more 'negative' looking to tear folks down, but I largely got over that.
I do take a special pleasure in complimenting women, especially attractive ones. It's a weakness of mine. If the delivery is good, and the content is good, it usually goes over well.
I find it's good to compliment women on something outside of the obvious "you're hot" type (no duh). good ones are to compliment them on their hair ("you have beautiful hair", or "I love your hair"), or their style ("that outfit looks great on you", or "you have an amazing sense of style")...best of all, if you run into one of those ladies who just radiates good positive energy and has a great smile, tell them. "You light up the whole room with your smile", or "You just radiate positive energy". I've done all of those, and it's always gone over well, especially as I'm not using it as an excuse to get their phone number.