Is there any easy way to make a basic shape that looks something like this?
Yes, you can do it in a few steps:
(updated as per PG math's advice)
How to add the ridge:
@GiantCowFilms posted a great answer, and I would recommend reading that, if you haven't already.
It should be mentioned, though, that Blender has a built-in "capsule" metaball.
Simply press shift-A, hover over "Metaball", and you'll see the "capsule" shape there.
Note that this is a different kind of shape, and should probably be converted to a mesh using Alt-C.