I currently have dual boots with VectorLinux and Windows XP on three computers and over the years I've had dual boots on several computers. I've never come close to wiping out Windows or being unable to start Windows.
You do need to know what partitions are what in Linux terms. Linux doesn't use drive letters like C or D. Linux uses things like /dev/hda (first hard drive), /dev/hdb (second hard drive), /dev/sda (SATA drive or SCSI drive), and also uses numbers to show what the partitions are on the drive, like /dev/hda1 (first primary partition on the first hard drive), /dev/hda5 (extended partition on the first hard drive). I recommend reading more about this before you start. If you just plunge in without knowing how Linux identifies partitions, you *could* mess up or wipe out Windows. People have done this. But if you understand Linux partitioning, you will not have problems.
When you install VectorLinux, you will be given the chance to use whatever partition you want for Linux and it will not bother Windows if you choose the right partition for your Linux installation. As part of the installation process, you will be given the chance to run a partitioning program. With the graphical installer offered with VL 6 Standard, the partitioning program is GParted, a very nice graphical program. With the text installer offered with VL6 Standard and the only option in VL6 Light, the program is cfdisk. It is a text program, not graphical, but is easy to use IF you understand how Linux identifies partitions. You don't need to use Partition Magic or similar if you want to use your Drive E for Linux. GParted or cfdisk will let you pick that partition, delete what's there now, and create a Linux swap partition of about 512 megs and use the rest for VectorLinux. The installer will then move on and let you pick your newly created partition and the file system you want on it (such as ext3 or reiserfs).