It deleted some regular images as well and did not stick to ads, navigation areas and margins.
I think, you should improve it by either adding a button at the top that allows showing all deleted items. If an item is deleted wrongly, there should be an undelete button to allow restoring it.

Another issue is the fact that you allow deleting the whole external DIV obviously. There are often some items within that are ads that cannot be deleted without deleting the whole DIV, which is a petty.

I think that you should learn from Lizard, which allows getting into internal DIVs and deleting them individually.