There are many on this forum who know lots more than I do about computers, about linux, about Vector Linux, about partitioning, and about installing Vector 6.0. So take these suggestions with a grain of salt and use them only as a last resort. I admire you for tackling this install on your own. You are doing right by learning about partitions before you proceed. And, since you are interested in wiping out Microsoft Windows altogether, you are unlikely to cause any serious problems. If the install does not work, you can just try again until you get it to work.
As my experience in loading Vector linux might be of some help, I proceed:
I have not yet figured out the new GUI installer, so when the install screen first comes up, I type "linux." That takes me to the old installer. When I get to the fdisk partition screen, and start fdisk, I am presented with two options....one (I forget its exact name) allows you to start with blank partition and the other allows you to use existing partitions. Unless for some reason I want to save something on the hard drive, I choose the start a new partition option and that takes me to a screen which allows me to make new partitions, from scratch. I first choose a swap partition roughly twice the size of RAM, next a root partition, which I make bootable (for programs) of roughly 10gb (if the drive is big enough) and finally I make the rest (third partition) the home partition (for user data). I then type "yes" to save the partition. I understand that typing "yes" wipes out everything that was on the hard drive. I then quit the partition program and reboot, so the machine will recognize the new partitions.
On reboot, I type "linux" again at the initial screen (to get to the old installer) and start the install again, this time not choosing the fdisk option, but instead choosing the install Vector linux 6.0 option. From there, usually I can just follow the prompts.
Something like that. I don't have a computer here at home which I can practice on now or I would be more specific. The above is just from memory and should not be used except as background.
Don't hesitate to post when you reach a point where you are not sure how to proceed.