Whilst this thread might now seem a bit old, in fact I have just re-read the entire thread with particular interest upon Virtual Computers.
My initial research (mentioned earlier in these threads) mentioned (correctly) that Vista Home premium is not a supported operating system for the purposes of
Microsoft Virtual PC 2007 HOWEVER I am very happy to say that I ignored the message that pops up during installation to tell you it is not a supported system and carried on regardless. It installs and runs perfectly. You get the same message box pop up the first time you create a virtual machine - once again ignore it and also tick the box "Don't show this message again."
No problems running Virtual PC on Vista Home Premium - it might be due to the installation of Service pack 1 that it now works. I recall reading that somewhere. You also have an alternative Virtual Machine Program which I consider is more powerful than the one provided by Microsoft.
Virtual Box This one is also free and has more settings that you can set yourself than the one from Microsoft. It will also open a "Virtual Hard Drive" created in the other one (Virtual PC) and can even accept "Physical Hard Drives".
(In fact I am writing this post from within a Virtual machine Right now)
I tend to use Virtual PC (Microsoft) for the Microsoft range of operating systems - Windows 3.11 (Windows for Workgroups) - Windows 95B, Windows 98SE - Windows ME - Windows 2000 - XP - NT4 - Even a second copy of Vista!
I tend to use Virtual Box for Non Microsoft Systems - SUSE - Knoppix - Mandriva - Ubuntu - Solaris - Fedora - Linspire - MCN - Xandros.
Regarding someone's earlier comments about licensing. Microsoft Systems will require activation (as always) and so you will obviously need the appropriate serial numbers. Microsoft do allow their systems to be run inside virtual machines - no doubt why they provide Virtual PC.
Virtual Box Screen shots
This article gives a step by step guide with screen shots and also a video.
Installing Ubuntu as a virtual machine
Whilst that shows how to install a Linux system, you do much the same sort of thing to install Windows XP. Once you have XP available you can now install MediaStudio and any other programs that just don't gel with Vista. I must say I was quite surprised with the results - Turn on "Full Screen Mode" and if someone walked into your room and sat at your computer, they wouldn't even know they were using a virtual machine.
MORE IMPORTANTLY.
If you either wipe your hard drive or create a dual boot system upon your computer that came pre-installed with Vista, you might have a problem finding drivers for your video and/or sound cards. This is not an issue with a virtual computer, the Virtual PC / Virtual Box Software acts as an in between and feeds to the guest operating system dummy Video/Sound and network cards. It also feeds to that guest system the necessary drivers for these Video/Sound/Network cards.
So you will get sound, a decent screen size - often the same as the Host operating system and of course you get out onto the internet.