Ok,

My computer when I go to shut it down, it freezes up and wont shut off. I have to manually shut it down by either turning off the power or holding in the button until it shuts down. What could be causing this?? Has anyone else had this problem? It has Win XP SP2, 1 GB ram, 1.6 gig processor.

On my laptop, it usually laged ALOT when I had alot of background programs running, its too much for the computer to shut down at th same time. Try going to the task manager and manually "end program" for anything you know is not vital (ipod related, quick time, nter stuff, yada yada) as much as you can, then try shutting down again. If it goes, then you know your problem.

im probably going to be no help because this happened so long ago and i dont remember a whole lot of the information, but something like this did happen to me until one day my computer would not turn on. i took it to some computer shop and they evaluated it and said (i think) there was some damage to the harddrive or something like that. turned out they had to repair it and i pretty much lost all of my information on my computer..music and pics.

like i said, i doubt im any help...im sure someone else will shed some light on the subject

If what edxmon said didn't help, you should backup all your personal documents and just reset the computer back to brand new and start over. That's what I would always do when I had little annoying crap like that happen to me.

you probibly have a process that fails to stop before you shut it down, so it takes forever. Usually if you wait awhile it will say something like "blahblahblah.exe failed because computer is shutting down" or something of that nature. usually if you figure out what program is causing it you can fix it without having to reinstall.

Same thing happend with my computer I reinstalled everything. It sucks but it will be smoking fast when you are done I reinstall every 6 months. If you have never done this do it and thank me later. I found it helps to have a portable hard drive just dump what you want there then format your main drive.

I like it when my computer boots in under a min.

Although a reformat/reinstall would solve it and is a good idea to do every once in awhile, unless you have all your stuff backed up, you'll lose everything on the machine.
Going by the specs, the computer is a few years old and you've probably collected a whole bunch of crap you don't need.
Start by going into the control panel and going to add/remove programs. Get rid of everything you don't need.
Then, after a restart, hit the "START" button in the lower left corner. Select "run". type "msconfig" (w/out the quotes)and hit enter. Select startup. Click disable all. Go back through the list and find the line for your antivirus software and make sure there is a checkmark ONLY next to that one and hit ok. Then restart.