The audio codec looks fine. The video codec is h.264 which is usually good for iMovie, but there can be variants that iMovie cannot handle. Another interesting thing about the h.264 is that it is anamorphic, which means it stores as 1440x1080, but simulates 1920x1080 by using rectangular pixels.
If I were trying to make this work, I would try converting it using a free tool called MPEG Streamclip, available here. I use the Beta version. http://www.squared5.com/svideo/mpeg-streamclip-mac.html
Drag your clip into MPEG Streamclip. Then click FILE/EXPORT TO QUICKTIME. For Compression, choose Apple Intermediate Codec. Leave the audio codec unchanged.
For Frame size, choose 1920x1080.
Check Interlaced Scaling, and for Field Dominance use Upper Field First, but if it looks bad, you can try checking "Deinterlace Video".
Click Make Movie. Give it a name and store it where you can find it.
Now try importing into iMovie using FILE/IMPORT MOVIE.