Many sites weren’t of any help at all, and some replies to this question on forums were met with, “Uninstall the program”, which is perhaps the stupidest answer of all.

So here’s the resources I finally used, so you don’t need to look anymore.

Removing “Send To” Entries:
Customize the Windows Vista Send To Menu - Simple, easy, and won’t break your computer.

Removing “New” Entries:
Clear Unwanted Entries from Explorer’s New Menu - For the more advanced only! You’ll have to edit your registry for this, but it’s relatively straightforward.

General Menu Customization
Fast Explorer - For the more advanced only! It was useful for getting rid of one of my general context menus that popped up on any file or folder I clicked for an archive program I used.