How to tune Notes on OS X to use plain text or not to reformat quotes?

Solution 1:

Notes

Notes.app in OS X 10.10 can do all you request:

  • Font colour, size, and family can be set through the Format menu.
  • Substitutions and smart quote behaviour are managed through the Edit > Substitutions sub-menu.

Screen shot of Notes.app in OS X 10.10

Beyond Notes: Text Wrangler

If you need more than Notes.app offers, try Text Wrangler from Bare Bones.