It says that I shouldn't update it just yet because my purchases from my iPod could not be transferred. It says to go to "store" and select "register this computer" but I don't see it on my iTunes or App Store on both my iTouch or computer.
Answer on How do update my iTouch 4.3 to 4.3.2 on iTunes?
That warning is coming up because you have not authorized your computer.
Here is how to solve it:
1. Turn on iTune
2. Locate Store tab on the left top corner of the iTune (it should be with File, Edit, View, etc)
3. Click Store tab and click authorize this computer
4. You might have to log into your app store account
5. When its done you can left click your Ipod (it has to be plugged in as you should already know) from the device section and choose to transfer purchases
6. Now the job is done, you can update your iPod and enjoy the OS 4.3.2 :)