Portions of Movie are UPSIDE DOWN

I have downloaded a movie that was originally .FLV and I have converted it to .WMV using Freemake (I want to ultimately play it on a standalone DVD player). It is 9 min. 49 sec. long and generally plays OK except for 5 portions where it has been flipped upside down for about 1 minute (each portion). It begins the right way up and at 1:01 flips upside down for about 60 sec. where it resumes the right way up. This is repeated at 3:03, 5:05, 7:07 and 9:09, all for approx. 60 seconds each time. I want to correct this before burning it to DVD. Is there any good FREE editing software that can do this? I can edit the upside down portions out of the video with Freemake but I want to re-insert them once they have been flipped right side up? I know that Windows Live Movie Maker has a "Rotate" command but it doesn't work for selected portions. What can I do? I am using Windows 7 Pro. Thanks!

P.S. I read in this thread that AviSynth may be able to correct this problem.