I think you are confusing the functions of what an internet browser does. A Browser is used to access websites. Google, CNN, wikipedia, etc. You can use it to access your email if your email has a web based interface you can access (like gmail.com, or yahoo.com, etc.). A browser does not power microsoft word, that is a separate program that doesn't depend on the browser you have installed to run. Long story short, install Firefox, try it. If it works for you (and it's going to be worlds better than IE8 which is the latest windows XP can use) keep it. Nothing else on your computer will be impacted.