The deal that forced Microsoft to offer a choice of browsers for users of windows has / is coming to an end according to the BBC.
http://www.bbc.co.uk/news/technology-30501518
There are several alternative browsers avaialble
Firefox
https://www.mozilla.org/en-GB/firefox/new/
Chrome
Seamonkey
http://www.seamonkey-project.org/ This seems to be a whole suite of internet utilities. (browser, mail, chat etc)