My iTunes (Windows XP) is not syncing to m iPhone 4S

I have been trying to sync my phone with iTunes for days and everytime I try one of 4 things will happen.

1. It fails to sync with an error message

2. It gets stuck on 'Waiting for SYnc to Start'

3. It gets stuck on 'Preparing to sync'

4. It will sync about 20 songs before freezing & having to start the sync all over.

(Note: Number 4 happens about once every 50 times, so I can't just keep doing that)

This is my first post & I am trying to be optimistic and hope to get a solution within the next few hours, but let's see:

BEFORE YOU ASK:

MY COMPUTER, ITUNES, AND IPHONE ARE ALL UP TO DATE