I believe that computer in particular is close to ten years old. If memory serves correctly it's got a 75 MHz or 90MHz processor in it, a PowerPC 603 series processor. Probably has a 4 or 6X CD-ROM and somewhere from 800MB to 1GB hard drive.
Edit: Saw that someone posted a link above.
The 62xx/63xx are amongst the worst computers ever made by Apple. They were filled with quality control issues, including faulty logic boards, RAM, etc. They were also very unfriendly at servicing, expanding, etc. I've got a 6300CD which sits at home in the cabinet. First Mac I ever had, so it comes out every so often - rock solid, though.
The power key is at the top right hand corner of the keyboard. It looks like an equilateral triangle of some sort, tilted about 45 degrees. This is assuming you have the Apple Extended Keyboard (I or II) with the isolated power button, the delete/insert/page up/down keys, etc. If you don't, the power button should be at the top of the keyboard, an isolated rectangular button with the same triangular symbol.
The application you're looking for should be in the following directory, if memory serves correctly: CD-ROM/Utilities/Drive Setup. It will give you a listing of all of the logical drives on the computer - select the hard drive, and hit the initialize button. That should do the trick. One thing about these computers from the past is that software problems are notoriously easy to fix, something we certainly can't say about its Windows counterpart at the time...