It can't pass a virus to my computer?
No.
Why?
Because you can't get a virus on the iPod touch and files (virus infected or not) cannot be transferred to it unless you take deliberate steps to do so (i.e. installing 3rd party software to do it).
Does it only upload things purchased on my iPod?
It only uploads things purchased from the AppStore or iTunes Store or pictures you have saved off the internet.
Couldn't an app contain a virus?
iPod touch Apps can't run on anything other than an iPod touch or iPhone, so would have no effect on your computer. There are no viruses for the iPod touch. If an App did become infected by a Windows virus (which is extremely unlikely, and could only happen on your computer, where it can't be run anyway), it would no longer run on the iPod touch.
Windows viruses cannot affect the iPod touch.
Doesn't accessing the web download information?
The Safari web browser cannot download anything, except pictures - it just views websites.
