Of course you can. Just get a partioning utility, breake the hard disk into separate partions and load the separate OSs into them.
Sounds like a problem with Windows XP. What you should have tried to do is take the original hard drive, put in the xp install disk, to the install, choose to format the hard drive, and then continue with the XP install. BTW: XP > Vista. Linux > XP. You should install Linux, instead of XP.
Yes. Actually, there is no need to remove the hard drive. You can format the existing hard drive and install XP on it as well. Note: Yes, you can there is no need to remove the hard drive. You can format the existing hard drive and install XP. and also you can install both opreting system single computer. XP and vista both.
Yes, you certainly can. Install Windows Me first on one of the hard drives. And after that install Vista on another hard drive. If you do reversed multiboot will not work. And you will have to edit boot.ini file manually which is not that easy.
Install Win XP on the first hard drive, then install Vista from Xp and on question about "what kind of installation do you want to have?" Answer "separate" installation. When it asks you "which hard drive are you going to use?" Choose the second one. Vista will create a boot list automatically.
Install Vista first. During the installation of OpenSUSE, you will be prompted if you would like to partition the hard drive to make room for OpenSUSE, or format the drive entirely for OpenSUSE. Make a partition of at least 6 GB, plus a swap partition of 1 GB. The installer will automatically install a bootloader known as GRUB, which can boot Vista or OpenSUSE at your choosing.
at least 15 gb
No, you only need a bootable DVD drive and enough hard drive space.
A 20GB hard drive with at least 15GB free space.
You should be able to install it normally I dont see why Vista would stop you. Make sure your in your Administrator account and that you have enough space on your hard drive to install it.
If it has the minimum RAM and hard drive space, you can.
Yes. To achieve this, you need to shrink the window partition so there is space for the Linux partition on the disk.
When selecting the drive you wish to install the OS on, simply select the external HDD.