Hi Debs,
As you probably know, I've been running Linux happily for a while now. As such, I feel as if I "ought" to be able to advise you on this. But I really can't... Until recently I've been running Slackware... but I haven't kept it upgraded. My old piece of sh^H^H hardware had very little memory. 500Megabytes seems like a lot to an old DOS-head, but it's not enough. If I'd planned to keep that computer I would have put more memory in it but I planned to replace it "pretty soon" for... about 15 years. So I'm not familiar with recent Slackware.
A couple years ago my daughter gave me her old computer. I asked a buddy "have you got that 64-bit Linux disk at hand?" What he gave me was Mint. I had the strange experience of running up against a Microsoft EULA! I would have said "sure, I agree" but it didn't give me a chance - no click, nothing else. Hung there. I don't claim that's typical of Mint, but I had a bad experience with it.
Around the first of this year, my old computer would boot no more. I had a bad cold at the time and "wasn't in the mood" so I had a friend install Slackware for me. He couldn't get it to see the net. If I'd gotten into it, maybe I could have... But he installed Debian, which he'd had good luck with and it "just worked" so that's what I'm running now. Can't say I especially like it... or dislike it.
I joke that "Ubuntu" is an African word meaning "one ring to rule them all" - meaning that they want to be "the" distro everybody uses. Really it means "Human". Redhat also wants to be "the" distro. Ubuntu is alleged to be "easy". You could do worse, I think, but I don't have actual experience with it. Try one, and it it gives you trouble, try another.
I think these days any of them are easy to install (won't ask you what your horizontal refresh rate is, like the old days) and would be "close enough" to Windows that you'll figure it out easily.
One thing you'll soon learn if you don't know: the GUI is not part of the OS - it's a separate program that acts as a "server". I hope you'll be happy with "console" programming - at least for a while... I think you'll like Linux - I hope so!
Best,
Frank