Is there any way to force Visual Studio to copy selected code to the clipboard as unformatted text?
When I am copy-pasting code into Word or more often Outlook
From this blog post I got these instructions for getting rid of the black background when copying & pasting out of VS with the 'Dark Theme' activated, but the html in it can be tweaked to alter the rest of the formatting as required (e.g. set all text to black).
If required, install Productivity Power Tools
Open Tools → Extensions and Updates
Select Online (Visual Studio Gallery) and search for Productivity Power Tools 2012/2013
Download and restart Visual Studio when prompted
Productivity Power Tools Settings
Open Tools → Options → Expand Productivity Power Tools select HTML Copy
Change the BeforeCodeSnippet option to:
Change EmitSpanClass to: True
Check EmitSpanStyle is: True