what else do you want to know?.
This Info is a good start and was not evident in your first post...
... I am using a lot of storage for ITunes TV shows and Movies. I would like to view them again later but don't want to tie up stoage in the meantime.
See here for Moving and Using iTunes on an external Hard Drive.
Copy your ENTIRE iTunes FOLDER to an External Drive...
Full Details Here > http://support.apple.com/kb/HT1751
Have a look at these 2 Videos...
To Operate iTunes from the External Drive...
Start iTunes with the Option key held down and guide it to the new location of the library.
Although you may currently have the right to redownload most content on demand (audiobooks are the obvious exception) content can be removed from the store at any time by the rights holder, in which case all bets are off. Best practice is to keep your own local backup. All iTunes content should ideally be in two locations, your main library and a backup, iTunes in the Cloud and any copy on a device is a bonus, Likewise other personal files should be stored on multiple, separate, drives.
Moving the entire library to a separate drive makes it easier to backup and move again later to a new computer or drive.