If you follow the rules to a T (ship only to confirmed U.S. addresses, ship with tracking, require a signature) you're covered in the eyes of PayPal.
I've probably sold 5 laptops and (easily) 10 phones for myself and friends on eBay.
Cover your bases, require PayPal and a confirmed address. Don't budge on these points and you'll be fine.
PROTIPS:
* Absolutely start with a $1 lowest bid, no reserve. The market will bring your laptop up to acceptable prices.
* Include as many words and pictures as you can in your description. I routinely just copy the specs from one of the tear-down sites for my exact model and paste them in. Buyers find comfort in knowing exactly what they're buying.
* Take as many hi-res pictures as you can. Don't worry about the scratch. Buyers find comfort in knowing exactly what they're buying.
* This is hugely overlooked: Make your auction end on a Friday or Saturday night around 11pm EST. This is when the nerds with money are sitting on their couch putzing around eBay looking for a new lappy.