I was on iTunes today and see there's a Featured iPhones Game App called "Spider: The Secret of Bryce Manor" that looks interesting and got a lot of good reviews since it's release August 10. Not too expensive, (2.99). It's by Tiger Style Games. Looks like it could be a bit addictive. Nicely done YouTube video of it on their website along with more info.
There's a zombie shooting game called "Alive 4-ever" (.99) that has scored pretty high among users too.
Walt Disney has a The Nightmare Before Christmas Jack's Pack of 10 wallpapers (.99). It includes the song "This is Halloween" from the film.