But if you really want to put it on a disc I'm not sure how you would do it.
Archive functionality (right click on an application) in Impulse; with the caveat that you'd need Impulse to restore said archive, and additionally that at present Impulse can't quite do so totally offline, as it requires an initial login first.
You also have the option of download and archive when an application is not yet installed, which is the preferred method simply because you can't make an archive of an installed application on say XP and transfer it to say Vista-or vice versa. (The download and archive method does work in this instance, though.)