"This is so old it doesn't have any USB ports. :-/" - Stilly
You could still use your old HDD in an external USB-powered enclosure and connected to new computer, which presumably does have USB. Then you could reformat/re-write data over it to your heart's content &c and return it to your old notebook, bearing in mind what people said above, or keep it as extra storage.
http://www.misco.co.uk/applications/searchtools/item-Details.asp?EdpNo=275993&sourceid=2003 for an example external case.
I've used an external enclosure to make use of a 20GB and then a 40Gb HD when I have upgraded my powerbook hard drive to bigger sizes, so they are useful. But it would be quite a bit of faffing about in order to rescue a 2GB drive, esp as there are now 10 GB and more flash drives available.