After spending hours on different forums to find the solution to this problem, I was finally able to work through it using this page (drupal.org/node/360836). The difference between that article and this is that I changed the word 'variable' to 'dr_variable' to match my SQL table names.
1. Go into the PHPMyAdmin dashboard and navigated to the database I wanted to clear.
2. Click on SQL tab and entered the following:
SELECT * FROM dr_variable WHERE name like "cron%"
3. Disabled all non-core modules.