Since there is no "more modern browser" than current versions of IE, anything that demands that you install "their program" instead of what you have is quite likely another scam just like the ones that insist that "your machine is infected and we are the only ones who can fix it." Any time you see "You must click here or bad things will happen" you should read it as saying "Please click here and let us f*ck you."

If you think you need another browser, you need to go to the site that owns the browser, and get it directly from there.

If you're running Windows, IE is a necessary part of the operating system, and you must have it installed in order for other functions to work. You can hide the browser functions, and never see it, but it must be still there "on the inside" in order for the system to keep running properly. In order to get security updates to the system, you must keep your IE updated so it is best to have one of the recent versions, and in most cases at present IE7 is probably the best choice for many users. IE8 is still new enough to have a few bugs when installed on WinXP or older systems, but they've been fairly minor, and it may be your best choice if you're running Vista or Windows 7. You don't have to use IE to browse, but it must be installed.

You can install as many browsers as you want. Each browser may look a little different, and some of them require that you pick numerous "add-ons" to get all of what you want them to do. All of them require that you learn how to run the one you choose to use, and once you learn how to get the best results you'll probably like which ever one you worked the hardest on.

Although I hear rumors that some sites don't work with IE, I've never encountered a legitimate site that I wanted to visit that didn't work with my (current at the time) IE, but there's nothing wrong with having another browser if you think it's a more comfortable thing to do.

John