None of firefox, IE, or Chrome have advertisements.
That is either yahoo, or more likely, yahoo toolbar for which I can see no reason to have it installed.
I am almost ready to go back to Cox Cable
What does your ISP have to do with it?
I think the "problem" is two-fold.
There is a bit of confusion about several different things.
Your ISP merely provides you a connection to the internet. Oftentimes they will have a homepage, or profile, account etc information, but that is totally disparate from the service you are paying them for. They also often provide a e-mail address, but you don't have to use it, of course.
Browser
The browser is merely an application that views web pages. That's it. Google Chrome, Opera, Internet Explorer, Firefox, etc do not advertise. the toolbars you have installed are the problem with the browser, and the fact is that you, or somebody, installed those to begin with, perhaps under the false belief that they provide a useful feature.
Browsers provide favourites and bookmarks. Why not use the browser's built-in functionality for this? At this point it sounds like what you are using is causing you trouble, and yet you also refuse to switch. to another home page. There is nothing you can do to "fix" it; they changed it and now it's different.
Home Page
Your home page has absolutely nothing to do with either the browser, or (usually) your ISP. sometimes your ISP may set a home page for you if you get them to do the setup, but aside from that there is no "restriction" or rule that you have to use that homepage. Personally, I use google.ca as my homepage. and I keep bookmarks using the browser functionality specifically built for that purpose.
Basically, in a nutshell-
your ISP provides internet service which includes the ability to browse the web, a web browser provides an application for you to perform this web browsing, and a home page is merely the initial web page that the browser loads.
