OK, tips:
1) "Fairly Used" in the title makes it sound worn out - say "lightly used" or "barely used" (which the text of your auction seems to indicate). Also, say what system it is for in the title - you have a lot of room left there! If someone searches for "tony hawk project 8 360", which is how I'd look for it, they won't even see your listing.
2) Not such a great idea to put a starting bid of $5 wit a BIN so much higher ($30) - you are most likely going to get someone to bid the $5 and negate the money you paid for the BIN (which isn't much, but what's the point). You could AT LEAST have gone to $9.99 on the starting bid for the same price and that would dissuade a few bargain-scrapers from bidding low (note if no one bids on it by the time you read this you can still change it). I assume you wouldn't be happy to sell it for $5, so I'd make it $9.99. Either that or just go the cheap-ass way and start it at 1 cent with no BIN (total listing fees = 20 cents) and leave it to fate (it *should* go over $10 at least based on previous sales, but who knows).
3) Completed auctions for used copies seem to be ending around $16-$20. I would have done a $9.99 starting bid with a $19.99 BIN, or perhaps a $14.99/$19.99 start and $24.99 BIN if you want to push it.
4) Add a little more to the description. Is it complete with case and manual? Are they mint? Just because you only played it 4 times doesn't necessarily mean those things are true. Just put any doubt out of a buyer's mind by stating it all up front.
5) Add a picture of the real game! I nearly always avoid stock photo auctions. This would help with #4 as well.