If I click File | Email Page Location, Chrome puts a totally obnoxious "Fwd: " in front of the page's title as the subject.
How can I make this stop?
Short answer: Install the "Send this page as email" extension**. It's made by google and you can use either your default email client or gmail to send the page.
It sends only a link to the page, and not the page contents, if this is not what you want surely there are other extensions that will send the page contents.
I found this conversation on a developers mailing list for Chromium. It's dated from 2009 and states:
(*) emphasis is mine.
So the "FWD" is builtin into Chromium's (and therefore, Chrome's) internal code, and is not caused by the email software.
You have the following options: