Haven't enchanted my weapon yet, but worried it will no longer have it's attack power afterward. Is this something that happens? Or will I still be able to attack with my standard attack power, just without the enchantment?

Just recharge it with a filled soul gem when the charge runs out. Highlight it in your inventory, press T, pick your soul gem and away you go. Simples.

Your weapon will simply use your enchantment, and you will have your original attack power back. No subtractions, the weapon will be the same as it was before.

Thats what I was wondering, just looking for a way to rename my weapons without killing them.