I have an even older NoBo (NoteBook), very slim, therefore with both external floppy and external CD-Player connected via PCMCIA card (Sharp Actius A280 - PII-366, 64Mb Ram, Win98).
I've managed to install VL, older version 5.1 std.
I had the same problem as yours, with some additional limitations such as just 64Mb of Ram, but it is working reasonably given the limited hardware resources.
You will need to make an install from ISO image copied into the root directory of your Windows installation.
If you would have another Linux distro previously installed on your NoBo, it could be much easier, but I believe you can get it done from the installed Windows.
First of all, to make things easier, my suggestion is that you re-partition your HDD, using Partition Magic, either version 7 or 8. Repartitioning can also be done from within Linux, during the installation process, nevertheless it may appear more complicated if you are totally unfamiliar with Linux and also with hdd partitioning programs.
Since you have 20Gb hdd, I would suggest you to shrink your C: drive to 1Gb, keeping it as a primary partition.
After, shrinking C:, you should create and extended partition with the balance of the hdd space available.
Within this extended partition, you should create first a linux swap partition located at the beginning of the available space with 512Mb, than another brand new Windows partition formated either as FAT16 or FAT32 with about 2.2Gb (I'm suggesting this much because that way you may be able to play with 2 or 3 different ISO versions of VL, like VL-5.1; VL-5.8 or VL-5.9 copied at the root directory of this new Windows partition).
Place this new Windows (Fat16 or Fat32) partition at the very end of the unpartitioned available space of the hdd once this arrangement is just temporary, we will reclaim this space lather by deleting this Win partition after you get your VL installed.
After having the shrinked Drive C:, the new Linux swap partition and the new Win Partition, you will probably still have between 15 and 16Gb of free space on Your hdd. I would create than the two partitions required by Linux, which would one with 3 or 4 Gb to be the root partition for Linux VL (/) and another with the balance of the space (10 to 12 Gb) to be your /home partition which is where Linux VL will keep your configuration files and where you can safely save your data files.
Re-partitioning done, you will need to copy the VL ISO image or images if you want to try more than one, at that second Win partition which will probably show-up as either drive D or E if Drive D is used by your CD-player.
You will have to do it either by downloading the iso images directly from Internet or if you already have it done a CD burned, copy it from your CD-player into your new D or E drive, at its root directory.
Than you should follow the installation instructions from ISO image pre-copied at a Windows partition.