I wasn't able to disable "Automatically find new updates and notify me." The option was not there on the Install/Updates page. Perhaps eclipse workbench has changed since that answer was written.
However, running eclipse with the -clean option in my old workspace did the trick for me. The way to do that in windows is to first find the directory where eclipse.exe lives. You can go to the start menu and in the "search menus and files" bar, type eclipse. You should see the purple globe icon pop up under "Programs." Hover your mouse over it and it will tell you the directory it exists in.
Then... open "computer" or some other window from the start menu and from there navigate to the window where eclipse is. Click your mouse in the bar at the top where the directory is displayed (somewhere not on the text). That directory will highlight. Now type cmd. A black command window will open and you will be in the directory where eclipse is. At the command prompt (drum roll) type eclipse.exe -clean
eclipse will start. Make sure it is asking to go to your corrupted workspace and click OK.
Wait for it and soon you will know if your workspace has been uncorrupted. Yay!