Consider the advantages of adding a second drive to your system. True, replacing your present drive with a new, low cost, high capacity one would seem a better alternative, but... If you can pick up a used 1.3 gig drive for a coupla bucks at a flea market or you local computer dealer (he might have accepted it as a trade-in), then this is indeed the cheapest way to upgrade your storage capacity. If you are planning to update the kernel on a production system, but are afraid of breaking some of your apps, then it is a simple matter to copy your entire ~/, /etc, and /usr directories to the second drive, where they would remain pristine and untouched by the upgrade. If a few hundred megs would tide you over for a few months, until you finish paying off your new patio or gambling debts, then save those bucks until next year, when 20 gig IDE drives will be a loss leader at your local "Five 'n Dime".
Copy down the specs from the label on the drive. Make sure it's jumpered as "slave". Mount the drive in a spare drive bay, securing it with several screws. Attach an IDE cable from the IDE port on the motherboard.
It may autodetect, but don't count on it. Check the BIOS settings to make certain. Setting the 'LBA' option not necessary.
Boot up Linux and partition the new drive: As root, fdisk /dev/hdb. [primary partition, Linux native]
mke2fs -cv /dev/hdb1 [verbose output and check for bad blocks]
Decide where you will be mounting it and create a mount point. For example, if you will mount it as /mnt/drive2, as root, cd /mnt mkdir drive2 chmod 777 drive 2 [makes the new drive accessible to ordinary users.]
As root, mount -t ext2 /dev/hdb1 /mnt/drive2. If no error messages, cd /mnt/drive2, and try creating a directory and writing a couple of files. If it works, hurray! Continue to the final steps.
Add the following line to /etc/fstab: /dev/hdb1 /mnt/drive2 ext2 defaults 1 1