Newbie? Tired of Windows security failings? Crave stability? Want better comprehensive and smoother upgrades? What more choice; for free?
This is my guide:
Prerequisites: 384MB of Ram or better; basically. Else see Puppy Linux to replace old 98 machines.
You will also need to make a CD (or DVD if you have one). Else you can order a free one, and wait. Just be sure to "burn" the ".iso" file, as an image and not as a file.
You might start with your carefully selected version of Mint. Such as the new KDE version. There less to set up and you can install and play with ease. This will show you, what you are missing.
To cut to the chase, I still recommend www.Kubuntu.org with KDE (Yes, over Ubuntu unless you just prefer "Gnome", it's good too.)
With Kubuntu you have to add a few things that Mint does, out of the box; but it's not hard. The trick is, you just go on the internet and find the quick commands and learn the "switches" to check off; that let you add what politics didn't allow Kubuntu to do automatically; out of the box. In the end and after you are familar with the system, Kubuntu will better branch out and do more tasks taht people want to get done.
Now why would you add an extra step, even if easy. Because Kubuntu is better mold able to you exacting tasks and yet still represents taking care of the ground work, with it's progressive upgrades, better than anything else. It's also closer to the Windows UI, than anything else, right out of the box (Yet all that's customizable).
Kubuntu, like all systems, has it's cons. I my opinion it's the less of all evils, including Windows and OS-X. You can go all-out and just run Kubuntu (to maintain just one thing) or you may dual boot with you old Windows. You can do both. Find a good on-line tutorial; on how to pre-partition your Windows system (after backing your stuff up) using something like a "gparted" CD.