I am a computer technician for a University.
To "use printer offline" in Windows 7;
Open the start menu, then Devices and printers.
Right click on the printer you want to use offline and select 'See what's printing'
A print queue window will open. Click on the menu item "printer"
A dropdown menu will open with a list of several items. One will be use printer offline. Click it once.
If you open that menu again it will have a check beside "use printer offline". Click it again and you will remove the check.
Note: This is not the same as the printer being offline. That is when the printer and PC have lost communication with each other due to a network error, a sharing error or the printer simply being off. This is a setting that allows you to hold print jobs in your local PC print queue until you decide to release them.