Re: hard drive tester
you coul get an external USB disk enclosure, this would allow you to test them on your laptop.
However I suggest the for the price (~£100) you'd pay for that you might do better to go to cash converters or ebay and get a work station which will be much better for testing them.
You can't really test a drive inside of windows very well, at least I don't know of any tools that are available for disk thrashing.
However if you search for Hiotachi Drive fitness test you find an image for a boot disk that enables you to thoughally (spelling?) test the drive.
I recomend getting a new workstation because
1, it will be easier to swap the drives about.
2, you can have more than one drive connected and tested at a time
3, you'll be hard pushed to find USB device drivers that work under dos, which is where you'll find the easiest disk testing tools.
(if you are confident you could use the USB disk enclosure option and look for some tools in linux.)