I've never done a check sum on an ISO. But Mint's own ISOs were never compromised, so that I trust.
Unity is the product of years of well-funded focus grouped research, to be the easiest desktop scheme for someone who has never used a computer and knows nothing about them. Like grandparents, for example. Seems like a vanishingly small subset of users to cater to. They also wanted an interface that worked on both a desktop and a touchscreen mobile device, like MS attempted with Windows 8's Metro. Gnome went that direction as well with Gnome Shell.
I still like the standard desktop with a taskbar and a start menu.
B1: Canonical put lots of time, effort, and money into trying to make Unity the most easy to use interface they could come up with. You're exactly right. It's a heavy application though.
B2: Same here. That's what i like about the XFCE4 panel, it can be used as a dock / launcher from the top, bottom, left, & right of the screen with as many or as few applications as you like. It can be sized statically or set to automatically expand or go opaque. You can also bring it up on hover and hide it to reclaim screen real estate. Hell, you can even make it look like an Apple shelf launcher. More than one can be added to the desktop too. Full customization is the name of the game.
You may get a kick out of this article: http://www.tomshardware.com/reviews/fedora-16-gnome-3-review,3155-27.html
. I pretty much ditch things I can't customize to my liking. With DOZE, I learned how to hack the registry - not without some major f-ups though, but I exported the hives beforehand and re-merged when I borked them. For me, that's what's fun about computing, learning the guts of how something works, and then improving upon them to suit my needs.
Correction to my previous post:
Terminal: md5sum /path/to/file/from/root
^^^ this works on my version of 'nix ^^^ The following tutorial is incorrect regarding linux, but it gives you the basic gist for the major OSes. http://www.droidviews.com/check-md5sum-of-a-file-on-windows-mac-and-linux/
Replace md5sum w/ sha1sum to check the sha1. All files should have both. 10 seconds is all it takes to check to make sure of any files' integrity. Hope this helps.