Just wanted to let you all know the problem seems to be solved in iTunes version 9.02...  
Hello, I am experiencing this strange problem on my Dell Latitude E4300 with Windows XP SP3. Whenever I perform a sleep or hibernate cycle after a session of iTunes, it is no longer possible to start up iTunes. In the Task manager, there is a process called "itunes.exe", but the user interface for the program does not come up. Also, iTunes does not come up in the list of running applications. It doesn't matter whether i close iTunes or not before the sleep cycle. Moreover, after the sleep cycle and the attempt to restart iTunes, it is no longer possible to shut down the PC, apparently because the process itunes.exe cannot be stopped. Only a hard shutdown (8 seconds power switch) does the trick. After restarting, iTunes works again, until the next time the laptop is put into sleep or hibernate mode. I first noticed this with iTunes 7.5, then reinstalled this version (repair install)  without any improvement, then upgraded to the latest version (8.2.1), again with no improvement. Anyone with the same problem, or better still with a solution?  
Unable to start iTunes after sleep or hibernate (WinXP)