There's 2 women in my year out of 7 and it seems like we have about 2 women per year (haven't counted every class). On my interviews, I only saw maybe 2-3 women so I was very pleased that my program had a couple. You're right, for whatever reason, women just don't seem to be as interested in radiology.
There's no absolute ranking for the best places. Figure out where in the country you'd like to live, talk to some radiologists at your school, get a list of at least 30 places to apply to and check them out on the interview trail. Some places are better for the research minded, some better for the clinically minded person. So, just like the answer to the best medical schools, it depends on you and how you fit in. The most important thing is to see as much as you can and go to a program with a high board pass rate that you enjoy going to everyday.
As for residency, radiology is a 4 year residency but it required a 1 year transitional, prelim med or prelim surgery year before you enter radiology. Some programs provide you with that first transitional/prelim year, and others only provide you with the radiology years where you'd have to find your own prelim/transitional year (not a problem at all).
For residency, at least here, our radiology residents aren't on call that much but it all depends on the program. About once a week is the most demanding schedule and you always go home after your shift in the morning. As a radiologist you don't get to sleep at all on call and staring at a screen for 12 hours is exhausting. That's one of the reasons I chose radiology, for the work hours, although you will still work 50-60 hours a week as a resident.
I'm currently in my transitional year and I have 4 months where I'm on call every 4th day. The other 8 months I have no call and usually get weekends off. So far I haven't had a call month and I'm working about 50-55 hours a week, but will work harder during those call months. To be honest, my 3rd year of medical school was more demanding to my time than residency, but then again, I'm not in a surgical residency program. Typically the prelim medicine years have more call and the prelim surgery years even more call with transitional year being the lightest in terms of call. I also have 6 electives and I guess I could have elected to take say trauma surgery, but I've been through that pain in medical school, no need to hurt myself. Needless to say, all my electives have no call.
I'm technically not, nor is your friend a first radiology resident yet, but because I'm doing all five years at one hospital (at my program, matching into radiology meant you automatically got the transitional year) I still go to some of the radiology conferences, get all the radiology journals, am a member of RSNA and have access to the central PACS (the medicine residents do not), so I'm a pseudo-radiology resident right now (I get some perks).
For all the horror stories about call, they usually apply to those surgical residencies, OB/GYN and to a lesser extent the medicine residents where they have many more call months than I currently have. I'm also at a very good hospital where even the general surgery residents rarely put in over 80 hours per week. Again, depends on where you do your residency at. There's certainly many places that work you much harder.
