DIMENSION 8100 Dell computer : How do I open the case please ?

I bought a DIMENSION 8100 Dell computer from an auction.

The Dell computer has Windows XP and seems to have a CD rom drive and a CD rewritable drive.

I would like to transfer my 500 or so Microsoft Word 2000 documents from my old Windows 98 first edition computer onto the Dell hard drive.

The easiest way of doing this I think is to unplug my main hard drive from my old computer and plug it into an extra IDE socket of the Dell computer.

If the main drive of the Dell computer has an extra connector on its IDE cable, I will plug the main drive of my old computer and set it as slave.

Or if I am not certain of where to place the jumper, when I get down to it, I will unplug one of the CD drives of the Dell computer and plug in its place the main drive of my old computer.

Can anyone give me instructions on how to open up the case that the Dell computer is housed in please ? The case is Tower style.

I am hoping that I will be able to install Microsoft Word 2000 on the Dell computer since I have the installation CD. But if I cannot, does anyone know what best to do in such a case ?

I would also appreciate any comments on what I intend doing.

Thanks a bunch.