Delete stuff from “My Recent Activity”: just deleted from the log or …?
If you go to My Askville > Recent Activity and delete an “activity” that you had there it does not influence your comments, questions or answers. The only thing it does is that it deletes it from there and you won’t be able to see it there. It is actually not a bad idea to delete them from there since it just takes some space there and I don’t see any use for that, other than if you want to see when exactly you have left a comment or answered a question. For that you can get an approximate time by going to the question page, but that would be an approximate time. All questions, answers and comments can be accessed from “My Askville > History” and “My Askville > Discussions”, however some people delete their old “Discussions”. I personally do not delete those entries from “My Activity”.