If you're using Windows98 or below, yes. Otherwise, sorry you're outta luck. In their infinite wisdom, Microsoft has integrated iexplore.exe into explorer.exe, the base of the Windows operating system. What you can do, however, is set program defaults to use a 3rd party browser such as Mozilla as your default browser, instead of Internet Explorer.
Windows98 doesn't have IE as integrated into it as newer operating system's do. However, it was the first Windows version to integrate IE4 with the active desktop. I remember a rather old program (it's been years and years, so it would take quite a bit of searching to do it) that was capable of downgrading IE4 to IE3 in Windows98. IE3 ran as a standalone web browser program and was not at all integrated with the OS as IE4+ is.
No, nic_m_moon, you cannot completely uninstall it on Windows XP. You can disable it, but not uninstall it. Internet Explorer shares most of its files and functions with Windows Explorer, and without that your system quite simply wouldn't even operate!
There is a 3rd Party Product, however, which will remove most of it from your system, and make your Windows XP installation appear not to have Internet Explorer installed at all: