Other category filling up phone constantly finicky. iPhone 3G

Im having loads of problems with my iPhone 3G and Im not sure if they are related or not. Note: I have already reset the phone and restored it from a backup. The problem is that the phone is filling up with the other category when I check it in iTunes. When I reset from factory settings, it removed this other category, but it slowly built back up and filled up the phone so I cant sync it anymore.iPhone is incredibly slow, sometimes wont come out of sleep mode.Constantly locks up (screen goes black or just freezes) during calls and application usage.Periodically prompts me for a login to a shared iDisk calendar. Will go days without doing this, then start doing it every time I unlock it. Sometimes randomly during calls or app usage. This calendar is not password protected.I visited the Apple store today where they instructed me to wipe the phone AGAIN and instead of restoring from backup, just resync it with the phone. He says that the problem could be an app Im using thats filling up the other category. The apps I have installed are: UrbanSpoon, Slacker, Pandora, Shazam, AIM, PhoneFlicks, CoinToss, Wikipanion, Yelp, AllRecipes, Banking, Booworm, DoodleJump, Vampires, Papaya Farm, Flick Fishing, FlightControl, XRayFX PRO, Zippo Lighter, WobbleLite, photoswap, Koi Pond, Banner Free, StoneLoops!, WildWest, Paper Toss, NPR News, I Am T-Pain, and Zombie Pizza. I think these are all fairly popular apps, so Im wondering if anyone else is having this problem with a specific app that maybe I could remove to fix it?Any help would be much appreciated. iPhone 3G Mac OS X (10.6.1) 3.2.1 Software version