Thank you. ^.-
The reason for the ledge grab is an extra chance to catch yourself when falling. I'll look into the ledge grab window though.
You're not safe anywhere around the snakes. That's intentional. Platforms wont keep you safe. Keep jumping. Don't touch the snakes. (it's really just supposed to be the teeth, I'll check their hitboxes, something might be screwy there)
The start menu shouldn't shake that much, so I'll try to find out why it would shake more for you.
You're supposed to press the "action" button on the "New Game" icon (whatever you have mapped for "Down"), which causes the letters "ESCAPE" to fall and Bun to hop down to the first area.