One thing I discovered a long time back was just because an update was available did NOT mean that I had to accept it. Mint 6 was carefully assembled in its original form. Once you deviate from the original form, you may or may not have problems. If you stick to the Level 1 and 2 updates only, you have a system that has packages tested by Clem and the team. The Level 3 packages can break things in certain instances since they are designed for Ubuntu systems. That is what has happened in your case, I am guessing. One package messed something up. I have had that situation before, so I know the anguish. As you become more familiar and experienced with Linux, you can actually jump right in with the Level 4 and 5 packages. Though, for now, I would leave those alone.
So, you did a reinstall. You are back to everything being as Clem released it. Great. You can set your mintUpdate to accept level 1 and 2 packages. You can also set it to show the level 3 packages, but NOT enable them. This way, you can then pick and choose which Level 3 packages, if any, you may wish to accept. In your case, there is one package you do not want to accept again. Not sure what it is, either. You can have fun experimenting, or leave it alone and enjoy Mint 6 for a couple more months until Mint 7 is released. Have fun.