For seeing Java installed offline you can download the libraries from http://www.oracle.com/technetwork/ja...ads/index.html
You can also copy the entire contents from another 7 machine with the same version installed and make another attempt at the uninstall option in the Programs & Features to then try a second attempt at a fresh install using the online interactive download page seen at java.com: Java + You
Be sure to go with the correct download as well depending on which flavor of 7(32bit or 64bit) you are running.
For problems with the Windows installer itself type "msiexec /unreg" in at the Run command line and press enter to first disable and then re-enable by typing "msiexec /regserver" in at the Run text box there and press enter for that command. You can follow those two with the "sfc /scannow" command to run the system file checker tool. This is the usual method used for solving that particular error when seeing a bad install.