Afrodite,

We don't delete/remove accounts, we just close them upon member request but those have to go through admin and we have several security measures in place that we check before doing that. If they got into your account (which is your password is strong is highly unlikely) they could delete your gallery images, wishlist, etc.. Anything you can delete yourself if you are logged into your account.
We also have measures in place that would be able to detect if it came from someone different than yourself although we couldn't restore gallery images if they were deleted.

I don't think you have anything to worry about with your Renderosity account to be honest though.

Captain Jack, very good information! Thank you for helping