Yes, you can paste text from Microsoft Word, but you should do so by typing ctrl-v on your keyboard (as opposed to the right-click speedmenu paste option that is available on a 2 button mouse). When you use ctrl-v to paste, some special characters that Word uses for quotes, apostrophes and dashes are replaced with characters that are compatible with your browser.
Note: Some Mac OS X browsers don't support pasting into the editor using ctrl-v. If ctrl-v doesn't work, then first paste using the right-click menu. Then type ctrl-v to clean up the text.