It works on mine. Do you have any events that should be in there? If so, sign on to iCloud.com and delete them, as they may be corrupted. Then you can recreate them once the Calendar app is behaving again.
Sasdly not so far. I have lots of repeat appointments - they don't cause any problems elsewhere so why should they in March 2013? I had one appointment that was not a repeat. I deleted that in iCloud as you said. But still iCal will not open March 2013 in Month view. I noticed lots of other people are having the same problem and I found, like them, you can open it in any other view - just not in month view. It is a nuisance.
Thanks for your suggestion, though
It's caused by a bug because of daylight saving time adjustment on 31st March in to 1st April.
As a fix, delete any all day events you have for 1st April 2013. You can add them to a time i.e. mid-day to replace them.
Once there are no all day events on 01/04/2013 March will open in all views.
Let me know how you get on.