Okay, time for my report after a day of using Zorin. 
Doing the dual-boot install was fun (not!). Had to create two separate hard drive
partitions: one for the "root" install of Zorin (with a mount path of "/"), and then
another for the "swap" partition. The filesystem I selected was "ext4" due to what
I read on various websites as being the best.
I then booted into the Live DVD and selected to install Zorin from within that, as
I tried to install outside of the Live DVD before and it seemed to fail. All went okay
this time when in the live environment.
All my MP3s, AVIs, MPGs, MP4s and MOVs played perfectly with no codecs needing
to be downloaded. SWF files didn't play at first, but this was quickly fixed by right
clicking their icon, then going into "Properties", then "Open With", and changing
their default app to Chrome. (No downloading anything!). After that, double-clicking
SWF files would launch and run them in the Chrome browser for playing. Nice!
Next stop was checking out image apps. The default image viewer was nice (not
quite IrfanView, but that's another story) but did the job with nice zooming with
no pixelization. The default image editor is GIMP, which as everyone knows is a
powerful app that is often compared to Photoshop.
The default music player is okay, but nothing great. Will have to look for something
else soon. I need something like Winamp for Linux; I'm sure I'll find something!
Next step was to check out some app compatibility. I wasn't disappointed at all!
My wife's Excel budget spreadsheet is perfect with LibreCalc, no compatibility issues.
What else... oh yes: WINE.
The
best part of Linux for Windows defectors! If you
don't know, WINE lets you run a hell of a lot of Windows executables directly from in
Linux, without any work or conversion on your part. Basically, you just double-click
the Windows exe that you want to run, and it'll either run perfectly in Linux, or die.
So... what ran for me using WINE? Here's a very brief list of successful exes:
CCS64 (Commodore 64 emulator)
Doom 3 (at a good frame rate, too!)
Dynomite Deluxe (fun little game)
Hunting Unlimited 2009 (FPS)
IrfanView (favorite image viewer)
MAME (arcade game emulator)
Plants vs Zombies (addictive game)
Quake 3: Arena (another cool FPS)
Rollercoaster Tycoon (original game)
TrackMania Forever (car racing game)
Now, don't forget: all the above were native WINDOWS EXECUTABLES that ran! 
These are NOT Linux versions or SWF files or anything. Not exes inside a virtual
machine. I literally just browsed to my Windows drive and double-clicked the exes
like you would in Windows to run them. And lo and behold, they ran in Zorin just
like in Windows. Bloody incredible for a Windows user to see!
And the amazing bit?
PUREBASIC RAN! 
Yep, I can compile my Windows apps
using the Windows version of PureBasic in Linux. Here's a screenshot proving it:
All my test sources compiled perfectly with PureBasic for Windows... in Linux!
Wow. Just, wow. Granted, there are a few little problems, such as PureBasic's
toolbar not showing correctly (see the screenshot), but still, it's very impressive.
Final thoughts? I just need to work out how to launch apps with hotkeys,
like we can press Shift+Ctrl+Esc on Windows to launch the Task Manager. Anyone
know how I can do that? Other than that, I'm truly happy to use Linux now as my
main OS. I still need to dual-boot with Windows for a lot of apps, but I'd say 90%
of my time will be in Zorin now. I really am THAT impressed.
I'm so glad I don't need to worry about the future of Windows and all the BS that comes with it.
