The reason the text in the menu is $Menu.Help is because some files have been uninstalled. I recommend you run the installer for the previous version to install it again, then reboot, uninstall, reboot again, and then try installing the new version. Error 2605 has something to do with "server", so make sure you run the installer EXE from a local drive and not from the network.
If this fails, run the installer with the /l* option to get a log file as shown here:
http://www.classicshell.net/faq/#install_commandsAttach the log file here.