Ok so I'm level 18, I've unlocked some enchanting perks, I've got soul gems of every size (all with souls). When I go into my item screen and select a weapon to charge it says press T to charge. I do... Nothing happens. This is gettig REALLY annoying. Can anyone help?

Get a 360 controller!

No, but seriously, check your key bindings and make sure they haven't changed somehow. Also, I think you need to be in the item menu with the weapon highlighted, not just have it selected as your weapon.