|with the advent of card readers and usb drives it has become rare the OS is on c: anymore. Unless you are installing a much older driver/printer this is usually not a problem. Most installs allow you to decide where they will install or they read the %system% variable to know where to go.|
You can't change i: to c: without a complete reinstall.
With older software you can try coping the contents to a folder on i: and then find the install or setup.inf file. Edit it to change c: to i: and you should be fine.