Long story short, it depends on the daemon.

Debian stable is the kind of boring distribution I would recommend for such boring use ;)
(being boring is of course a big benefit in this case)

+1.

Debian stable and Slackware are the only two OS' that have always worked as expected for me.
Everything else has developed the odd quirk from time to time.

Odd quirks are fun. Certainly better than dumb quirks.

Well great. The discussion has gotten rather technical, so I don't think I can comment on much specifically, except that now people seem to be mostly saying bad things about Debian and sometimes Mint (isn't Mint one of the Debian ones?), which seems pretty much backwards from what almost everyone was saying up to this point, and I was really leaning toward Mint, but now I don't know what to think at all!

Well yes, Mint is based on Ubuntu that is based on Debian. I have not used Mint, but Debian and Ubuntu are vastly different experiences, so I expect Mint is different from Ubuntu - at least in some ways. Honestly, you are overthinking this. If Mint looks good, pick Mint. It's a popular and well supported distro geared towards new desktop users. Big community also means there's likely more documentation and active forums. It's gonna be fine. Distros have their quirks but they are not that different in the end.
And I like Debian. It's hugely popular and widely used, but it does have some design choises that are at times weird and make it unsuitable for some use cases. And really, with any OS you can run in to a problem that's extremely rare but sullies your experience, it happens. Has happened to me.

If this is your main gripe with Debian, it is indeed a good sign about its overall quality ;)

It depends on what you want.

For gaming, it is probably a good idea to go with a distro that releases up-to-date packages (eg. not Debian). Especially if your hardware is relatively new.

Someone mentioned trying out distros in a virtual machine. This is a great idea. Figure out what you like before you take the time to install on bare metal. When you do install it, if you are using the latest hardware, be prepared for possible issues if you are using a distro with old packages (Debian comes to mind again).

You can set up a swap partition, or choose not to. That's not a problem. I don't use one. In the case where you need more RAM, you can create a swap file of any size you want and enable or disable it with the swapon/swapoff commands without ever rebooting.

Arch Linux stays up to date and I always found it to be well put together. The only reason I stopped using Arch was their decision to adopt systemd. I wouldn't worry too much about systemd one way or another until you're comfortable with Linux in general, because any Linux system with or without systemd is going to be far more secure and private than running W10, or any Windows, for that matter.

Arch Linux is not the easiest distro to install, but if you are able to follow instructions from their excellent wiki, it is really not that hard at all. If you are new to Linux systems altogether, it's probably best to start with something easier like Mint, Manjaro, or I guess Fedora. Don't dive into something that you're going to be overwhelmed by and get turned off before you get to really try it out.

FWIW, I do all my gaming in Linux. I can get most things to work. These days, it's uncommon for a Windows game to not work at all under Wine. There are a few cases, but that's what your Windows dual-boot is for. Some games take some tweaking. I would recommend installing winetricks, which makes that a lot easier. appdb.winehq.org is a great resource for finding out how other people got certain games to work that don't work out of the box for you. DXVK is a Vulkan translation layer that drastically improves performance with DX9-DX11 games under Wine. Definitely recommend trying it out.

huppumies, you make some good points, and I do tend to overthink things, but only because I'm careful, and I have a history of somehow still making the wrong choices despite my overthinking, and everything blows up in my face, so I do everything in my power to at least try to avoid that.

drmsux, that's one of my favorite names! Anyway, it's good that the swap partition and file are optional, but are you sure that the swap file is NOT enabled by default? I just want to be certain, because if it is, I need to make sure to disable it. What's systemd and why is it bad? I'm not really worried about game compatibility, because I'll just use Windows for that, but Windows will be 100% offline, and the only thing that I'll really use Linux for is connecting to the Internet.

Any distro should work just fine for your use as long as your hardware is not super old nor too new.

Actually, I just thought of a few very interesting questions that I'd REALLY like answers to if anyone happens to know them and could please tell me:

A: How much space does Linux tend to use - in other words, what's the minimum reasonable size for a partition, if I don't really plan on installing anything on it?

B: Is it possible to install Linux onto a portable USB drive so that I can stick that in a port, turn on the computer and actually run Linux from that instead of having it on a hard drive?

C: If I were to use really generic or default drivers for everything, would I be able to take that USB stick and put it on any computer and run Linux without any problem of incompatible drivers? I'd really like for it to be able to run on any computer which is at least newer than a decade old or so, whether it's a PC or Mac. It doesn't have to run in any impressive way - it only needs to work!

Thanks a lot if you can answer any or all of those questions!

A. For Opensuse I think... it wants to do a 40gb partition by default but there is probably a way to make it smaller.
B.You can make a Live version of most linux distros, so you can test it out.
so then you put the USB in a slot and run it and the OS just works most of the time.
Anything you save to the flash drive will reset I think but you can save files to your main hard drive.
C. Unless there is something really disliked by the kernal or divers yes, at least in my experience.
If it doesn't work I find waiting a bit for more updates and bug fixes to come out to let it run.

A: As a rough estimate you can expect 10-15gb for a basic install.

B: Yes you can, unlike Windows, Linux let's you install it on any kind of storage. I actually did this once for a client who had a very bad PC and refused to even spend money on an HDD replacement. A USB got him up and running.

C: In many cases this will work, especially if the PC is a few years old, I have 5 PC's at home, all with different hardware but using the same OS, I cloned the same setup across all of them without issue. The only issue you might run into is with different GPU's. Nvidia tends to favor the officially closed source driver, whereas AMD and Intel can make use of Mesa which comes out of the box.

Being boring has its' benefits indeed :)

Debian Stable user here, (Debian 9 Stretch almost since release). It's quite old nowadays, but I've self compiled many packages to the point where it kinda feels a mini-rolling release. I even added Mesa 20.1.8 support and runs a Navi GPU.

Admittedly, it takes some time to get it up and running but once you do so, it's a real beastie. Never let me down in over 3 years.

Mint