img src="123/123.png"
style="width:99;height:99;border:0"
title= "yadada WHAT DO I DO IF THIS LINE GETS SO LONG THAT YOU CAN'T SEE IT ALL?"

I would like to write quite abit of info, but how do I make a line break in the title

and can I set it so that the title info don't fade away after 3 seconds?

Use n to break the title into multiple lines.

The title will stay visible for as long as the mouse is over the object that the title is attached to.