If you actually give Margaret Court credit for 62 slam titles, then that's definitely going to be the hardest record to break---in fact it's probably impossible. The thing is though, she really didn't have 62 slam titles because most of those titles came from before those tournaments were slams. And she also won close to half of those at the Australian Open, which most of the top players didn't even go to at that time. So the whole record is very dubious, but yeah, there's virtual no way that anyone could ever pass 62.
Also, some of the records you have there are only for the Open Era. For instance, Margaret Court won more singles titles than Navratilova. And Helens Wills Moody and Maureen Connolly both won more consecutive grand slam singles matches than Graf (although, again, those tournaments weren't really "slams" at that time.)
EDIT: Helen Wills Moody also has a longer match winning streak than Navratilova.