changing my default email editor from outlook to gmail

Not sure as to exactly what you're asking but I'll take a guess. If
you're interested in having email links (commonly referred to as
mailto: links) open up in gmail rather than outlook, this can be
accomplished in windows with the Gmail Notifier program from google.

http://toolbar.google.com/gmail-helper/

The feature you need will be an option during installation.

You can have gmail as your default mail application for internet mail
links by installing the Gmail notifiers from here
http://toolbar.google.com/gmail-helper/index?promo=gdl-en

You then right mouse click the envelope icon on the system tray and
select options, then select the Use Gmail for internet mailto: links
check box.

Cheers ZoOnI