It looks like as if your Installer.app or some of the surrounding components are broken (e.g. Install.framework). Have you tried to install something else that is using a .pkg installer?

To isolate the problem please try to launch Installer.app (you find it in Applications -> Utilities) and if it works do a right click on "Install LimeWire.app", select Show Package Contents and then navigate to Contents -> Resources and double click "Install LimeWire.pkg".