Any good Linux utility for checking and repairing hard drive?

[bluescreen]

We run a bunch of Suse Linux OS on our point of sale systems whenever we get a HD unreadable error or HD read errors and it doesn't boot up we just replace with a whole new CPU unit and never having to actually troubleshoot if it even was the HD or something.

I like to find out if there is any good Linux utility i can put on a USB drive boot up and test, repair, or even fix the HD.

Our hardware has no floppy or cd rom drive.

regards.

[till]

Knoppix is a nice Linux distribution to repair and recover systems. It can also be installed and booted on a usb stick:

http://www.knoppix.net/wiki/USB_Based_FAQ