Hi there
Virtualisation 101 (non technical)
1) Your computer system runs an OS (Operating system) which is loaded up when you switch on the machine (boot). This machine has its own set of hardware and after the computer starts up you can run your programs, browse the Internet, read and send email, play music / videos and a host of other things.
2) The operating system is the control program that starts when you switch on the machine and there are various "different" control programs that can be installed on the machine - usually one version or another of Windows or Linux. (We'll forget about Apple computers here for this discussion).
Unlike your programs you run on the machine only ONE OS can run at a time - even though you can run many programs at the same time like email, internet browser, EXCEL etc.
3) By a technique called Virtualisation it is possible now to run MORE than one OS at the same time. A piece of special software runs on your normal OS which has the ability to create some "fake" hardware (known as Virtual hardware) so another OS can be loaded on to the machine and run. This OS is known as a GUEST OS and it is designed so that it isn't even aware that it is running as a normal "Application" program". The software that enables this to be done is usually VBOX or VMWARE player. There are other pieces of software but these are the main ones and are free. You install one or other (or even both if you want) just like installing any other program on your running system.
4) When you start up the software you'll be presented with a wizard "Create Virtual Machine". This allows you to specify what "hardware" you want in the virtual machine (note this hardware doesn't PHYSICALLY exist as such but is "Virtualised"), and what OS you want to install. You then follow the on screen instructions and then install the OS -- just like a REAL OS -- if it's Windows you perform the same actions as if you were re-installing Windows.
5) For better Sound, Mouse, Video etc after the newly created machine starts you should install (from VMWARE menu or VBOX menu) an extra piece of software called VMWARE TOOLS or VBOX ADDITIONS. This fixes any problems with video resolution, jerky mice etc.
This OS behaves on the whole just like another totally separate PHYSICAL COMPUTER.
You can run it full screen or windowed - so you CAN actually have two versions (or more) of Windows running at the same time. It actually seems like another wholly separate computer - and it can be acessed on a LAN for example just like any other PHYSICAL computer. You can share its "Virtual" disks with your HOST machine or any other on a LAN. To the outside the VM appears like a normal computer with its own hardware.
6) I'd install LINUX first as a VM since it's FREE and no activations are needed --remember each instance of Windows needs a separate license / activation so unless you have an Enterprise or Volume license (VL) edition of windows running several windows VM's could be expensive.
That's the base explanation -- very basic -- but it's a start. Virtualisation is a great way also of testing software --if something gets totally hosed up just delete that VM and start another one. You only need ONE instance of vmware / vbox to control as many VM's as you can run on your machine.
VM's are quite RAM intensive though -- on your box I'd only run ONE VM with an allocated maximum RAM size of 1 - 2GB. CPU shouldn't be a problem unless your are doing a lot of video editing on your HOST or the VM.
There's all sorts of extra configurations and tips but this post should be enough to get you started. For Linux distros simply download any LIVE CD and in your Virtual machine configuration set the Virtual DVD drive to point to the .ISO file you downloaded -- and boot the Virtual (not the REAL machine !!) from the .ISO
As a beginner I'd stay away from HYPER-V. Practice with vmware vmplayer (my favourite) but others choose ORACLE' s VBOX --try both if you like - but remember Windows virtual machines need activations so I'd test a LINUX distro on both VBOX and VMWARE to see what you prefer. You can use HYPER-V when you gain a bit more practice with VM's - but you will have to UNINSTALL VBOX and VMWARE - these can't co-exist with HYPER-V.
One caveat -- although the Video facilities of Virtual machines have improved enormously in the last few years as well as the hardware capabilities of even quite small laptops - they aren't (yet) suitable for intensive gaming -- some older games might work. DVD and Movie playing though are just fine these days in a VM.
Have fun and welcome to the world of Virtual machines.
Cheers
jimbo