Not sure how an ipad renders the site sorry. I'm talking about using the little picture icon.On my iPad, no such check box, I only see these 3 options for check boxes.
Miscellaneous Options:
Show your signature
If enabled, your signature will be displayed below the message.
Automatically parse links in text
Will turn www.example.com into http://www.example.com.
Disable smilies in text
If selected, will not be replaced with