When selling old games with cardboard boxes (SNES, 32x, N64, etc.) I would always wrap them first with saran or plastic wrap making sure all the exposed cardboard is covered, then adding a layer or two of bubble wrap and securing it all with packing tape. In some cases you might even want to tape the game (Wrapped already of course) to a piece of spare cardboard (I do this for all CD's and clear plastic jewel cases to prevent cracks). It might sound like overkill but taking that extra time to wrap and package everything very well can save you in the long run and you greatly eliminate damaging the product so insurance wont be necessary.
I only list auctions that will end on Sunday-Thursday, 6-9 PM pacific time. That way you have people viewing and bidding from 6-12 no matter where they are at in the U.S. so there's a greater chance they'll be at home from work/school and will be able to bid in the last few minutes. Just think all you need is at least two people in a bid war to drive up the price of what you're selling. Another tip is to list similar items so they end in the same time frame, as well as offer a combined shipping discount (Make note of both in the item description so bidders will know). It might take some planning but can increase bidders' interest in items that people not be interested in getting simply by themselves.
For shipping I would recommend using USPS and printing everything out through Paypal Multi-order shipping. You get a discount on domestic Priority/Express Mail (Plus free DC) and you only have to pay $0.19 for delivery confirmation on First Class Mail/Media Mail/Parcel Post as opposed to $0.80 at the post office. BTW get DC for EVERYTHING mailed in the US (If you print labels out online its mandatory). Printing labels out at home saves a ton of time from having to stand in line at the PO and you don't have to fill in DC numbers or shipment info individually on Ebay if requested. If you plan on selling a lot of things you'll probably want to get a small digital scale to weight items at home, but you can get those for 20 or less.