With those symptoms, I'd try the following document:
(If there's a SpeedBit LSP showing up in Autoruns, it's usually best to just uninstall your SpeedBit Video Accelerator.)
My Apple TV works fine always, until there's any sort of update to iTunes. Then it takes FOREVER to load! Hours! And when it finally loads and the program starts running, it'll stop somewhere during the show and start 'loading' again. Talk about frustrating! As good as it is when it does work, I'm beginning to think it may not be worth the aggravation when this happens. May start looking around.