I'm not familiar with Slackware but usually rawrite is a DOS program. It's a case of running it and giving it the filename to write. It is the equivalent of burning an iso file, but to a floppy.
However, as somebody mentioned, can't you get the PC to boot from CD?
1 GB is a bit mingy for a Linux Install. It can be done but you'll soon run out of space. I'd give it at least 10MB.
Given your Windows/DOS background I would recommend Mandriva to start with. It has a lot of wizards which ease the pain substantially. (But not always
)
When I finally decided that Linux was usable, about 3 years back I started with Mandrake and have now switched to Debian. The problem with Mandrake is that the free editions tend to limit you, like if you want the latest KDE you have to join the club, and the paid for version is quite pricey. Also you need to upgrade when new versions come out.
Debian is a more comprehensive distro but, like most distros, can be tricky to configure.
Whatever you decide to go with, if you manage to boot from CD then just go with the flow and let the installer set up the partitions. Note that Since you're only giving Linux one partition it will need to be an extended partition so I hope that you haven't got a Windows Extended Partition (there can only be one extended partition per disc) as far as I am aware).