No. It is a safe program.
itunes
you can put it on a memory stick
plug it in your computer
iTunes for the computer is very different than the iTunes that you have on your iPod Touch. You can only have the iTunes from your computer when you download it for your PC (not for the Mac, there are two separate iTunes softwares) from Apple's website.
If you have iTunes program installed on your computer and the computer is connected to the Internet then you have all you need
you can og into your itunes account from the other computer
Your iTunes balance is saved server side. Long story short, as long as you log in with the same account on the other computer's itunes client, then yes.
Connect it To your computer on iTunes
Sync your iPhone to iTunes on our computer
Yes - go to http://www.apple.com/itunes.
no, itunes is very safe and causes no such problem towards your computer
Open iTunes on your computer and click on iTunes store