Budapest is the most beautiful city of those you listed. So for sightseeing or touristy stuff - go there.
For girls... many people here have said that if your sole intention for going to a city/country is girls, you will probably be disappointed. One week may be just too short in order to get girls.
But anyway - the prettiest girls from the cities on your list are in Kiev.
Cheapest fun to be had in Sofia and Skopje.
Bucharest also good, I hear, although I have not been.
Zagreb - there was a recent thread on that from a military dude stationed in Italy who drove there every other weekend and almost always hooked up - sounds like fun, too.
You got one tough choice to make, bro.
For girls... many people here have said that if your sole intention for going to a city/country is girls, you will probably be disappointed. One week may be just too short in order to get girls.
But anyway - the prettiest girls from the cities on your list are in Kiev.
Cheapest fun to be had in Sofia and Skopje.
Bucharest also good, I hear, although I have not been.
Zagreb - there was a recent thread on that from a military dude stationed in Italy who drove there every other weekend and almost always hooked up - sounds like fun, too.
You got one tough choice to make, bro.