Once formatted, you can try scan disk, but to be honest, you are far better off with an external USB hdd.
They are under 50 quid now, and you can place all your Acronis backup's there.
I use a larger 500GB model, but the link gives you an idea.
Over time, all media DVD's CD's etc. will become unreadable, and if you have used standard (non-rewritable) DVD's, you have, as you say wasted them.