1) Most MBA/Lauder classes do not take place on Fridays. For the most part, you will have Fridays "free." Because Lauder MBA candidates start earlier than most of their MBA-only classmates, they are able to get some coursework out of the way while enabling them to maintain a similar schedule to that of their peers.
2) This varies from course to course. The most common setup is two classes for 80 minutes per week for a full semester/
3) Also varies from course to course. The most common setup is two classes for 80 minutes per week for a half-semester. In global modular courses, the course may be completed in just one intensive week of study.
4) Varies depending on whether you are in your first year or second year, as well as what your personal preferences and objectives are. Most students take at least four classes simultaneously at any given point in time. Five is more common.
Take a look at www.wharton.upenn.edu/mba/files/MBA_Resource_11-12.pdf, which explains a lot more. Page 13 will be particularly helpful. Note that your class may experience some changes due to the new curriculum, but this gives you a general sense.
5) No required courses take place during the winter break, but some courses are offered during then (or span that time period in practice, as in the case of the Global Consulting Practicum course).
You can take a look at http://spike.wharton.upenn.edu/mbaprogram/calendars/academic_calendar_full1112.cfm to get a sense of how long winter breaks will last, typically. It is usually somewhere around two weeks long.