There are "lens cleaner" discs available, but in all honesty I'd say that you should just bite the bullet and pay the twenty bucks a new one will cost you. At Newegg you'll only pay about thirty (plus shipping) for a DVD burner.
http://www.newegg.com/Product/Produc...82E16827131031
Oh wait, you're British. I get so used to framing any comments about price that I make for Americans... they are the majority on the net. They aren't quite so cheap over here, but still not bad. You should be able to pick a good DVD Writer up from
Overclockers UK for about thirty quid. I recommend the LG GSA-4167BAL, since I've had the previous model in that series for some time, now. It's excellent, and I would buy from this product line any day.
Jam it back in, in the dark.
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