python-elementtree-1.2.6 : Is this really required by YUM ?
It looks like that's used to help with parsing XML-based repository information. I'm no expert, but I wouldn't risk uninstalling it.
m2crypto-0.16 x86_64 : Is this really used by YUM, I didn't think YUM connected via SSL ?
It looks like it supports it if you provide an https URL for a repository. It looks like m2crypto is used indirectly via the code in the python-urlgrabber RPM. I don't know Python, but glancing at the code makes it look like it should be smart enough not to cause a fatal error if m2crypto isn't present. So I suspect you can get away with removing it.