Brett,
For your Review, it sounds like the little utility that decides which language to present the setup GUI in is corrupt. You can work around this by going to your registry, open key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Autodesk Navisworks Review 2010 (32 bit) and copy the value of the "uninstall string" entry into a text editor.
So you will have a line looking something like this:
C:\Program Files\Autodesk\Navisworks Review 2010\setup\Uninstall.exe /P {CD4D81FE-EBDA-0000-B5BC-42988504F1F1} /M NW
Edit the line replacing "uninstall.exe" with "setup.exe", enclose the file path in quotes, and add /LANG en-US to the end of the line so you have something like:
"C:\Program Files\Autodesk\Navisworks Review 2010\setup\setup.exe" /P {CD4D81FE-EBDA-0000-B5BC-42988504F1F1} /M NW /LANG en-US
Then you can either save this as a batch script and run it or paste the line into Start->Run and run it from there. This should be enough to get the uninstaller up so you can uninstall.
Regarding your Manage uninstall, I would only expect to see that error message if you have uninstalled Manage except for some reason the installer has left behind the registry entries that make Manage appear in Add/Remove Programs. The thing to do would be to contact support and provide them with the installer logs from your Temp directory, and hopefully we can pin the problem down and give you a workaround.
HTH
Andy
Autodesk Employee