ipacialsection

There isn't an alsa command on my system either, so that's no surprise. But we'll need more information to track down the cause, such as:

• What (sound) hardware are you using? (try lspci | grep Audio)
• What happens when you try to play a sound? Does it get stuck loading / at 0:00, show an error, or just play silently?
• Is your system using pulseaudio directly, or via pipewire? (try pactl info)
• What shows up in pavucontrol? (Is it detecting your speaker, or just "dummy output"? Is sound muted, and can you unmute?) Try also alsamixer.
• If you installed non-free firmware, you should have a few lines like deb http://deb.debian.org/debian/ bookworm main contrib non-free-firmware in the file /etc/apt/sources.list. If non-free-firmware is not present, then obviously you have no non-free firmware.

Currently Elisa for my digital music library, and for individual files I prefer to use VLC. I've had good experiences with Strawberry Music Player (and its predecessor, Clementine), too, and am thinking of switching back to it. And when I was a GNOME user, I preferred Lollipop.

1. I believe there is still an issue with Windows deleting Linux bootloaders during some updates. You'll be fine if you install Linux on a separate disk, and even if you dual-boot on one disk and the bootloader gets deleted, there are ways to recover it. You don't strictly need to have separate data and OS partitions, and I've gone back and forth on whether I prefer it - it makes distro hopping and disk encryption easier, at the cost of potentially inefficient use of space and serious consequences if your OS partition fills up.
2. Disk encryption is very straightforward if you use separate OS and data partitions. You literally just tick a box during the install and enter an extra password. It won't upset Windows any more than a normal install does (i.e. Windows might think it's corrupted, but won't do anything without your input). With one partition for everything, it's still possible, but the encryption will be much weaker and handled by the bootloader in a somewhat clunkier way, and I'm not sure if Mint even supports that setup.
3. I don't have much experience with this myself, and certainly not on Linux Mint, so I'll leave this one to other commenters.
4. Synaptic is just a fancy frontend to APT, and I think Mint also has something called mintInstall, which was just an apt frontend back when I used it, but I think it also supports Flatpak now. It's entirely up to personal preference as to which UI you prefer. I do recommend you set up Flathub if it's not there by default, as it gives you access to a ton of useful apps that can't be packaged by Debian, Ubuntu, and Mint for various reasons.
5. Don't download software from random websites unless it's absolutely necessary. Chances are, their version either won't work well, if at all, or will break your system. Try APT first, Flatpak second, everything else is a last resort option. If a program you used on Windows doesn't have a (working, native) Linux version, try finding and learning to use an alternative that is in the APT repositories before downloading the Windows version and using it on Wine. Back up your most important files from Windows before installing Linux in dual boot, just in case you make a mistake somewhere. To answer the last question, stick to the default terminal emulator and Firefox installation unless there's a feature you really want in another one; the distro's developers picked them for a reason, after all.

I haven't had much experience with Kubuntu, but I do know it has more preinstalled apps, slightly older versions of those apps (where KDE Neon has the latest version of every KDE app the day it releases), but slightly newer non-KDE apps in the non-LTS releases, and is more beholden to Canonical's decisions, such as advertising Ubuntu Pro during upgrades or forcibly installing some programs as snaps. Kubuntu might hold your hand a bit more under certain circumstances, while KDE Neon keeps things simpler, but the difference in ease of use is not that significant, especially if you have any experience with Linux in the last ten years or so.

Any software that is in the Xubuntu repositories will also be available in other Ubuntu derivatives, and most likely Debian and all its derivatives as well. Only the official spins are likely to advertise Ubuntu Pro.

Mint XFCE is a good replacement, but I'm also partial to KDE Neon, which keeps preinstalled software to a minimum and is by far the most performant KDE distro I have tried. I myself use regular Debian, with KDE, though you can choose XFCE during the install.

VLC's file format support is amazing for a project that rolls its own codecs, etc, but it's missing some important features for me on the music front, primarily gapless playback and library management. I generally prefer to use software tailored to my DE. I've yet to find a better video player anywhere though; GNOME Videos and Kaffeine come closest and are a little easier to use, but are still far away from VLC's capabilities.

While this new display certainly seems better (in terms of being able to use 2x scaling instead of my current 1.25x), I'd honestly prefer to have a cheaper option that's just 1920x1280, so I don't have to use scaling at all. I don't care that much how "crisp" text looks.

Elisa is just the latest (and most actively developed) addition to the long list of music players developed under the KDE umbrella.

Right now I'd say the best open-source DAW for Linux is LMMS if you want to do everything just on your laptop, or Ardour if you want to use external instruments.

LMMS has some shockingly versatile built in synths, including a port of ZynAddSubFX, supports LADSPA/LV2 plugins, and supports using Wine to run 32-bit Windows VSTs. I'm unsure of Ardour's VST support, but it at least supports LV2 plugins. Either of those, if you install them through your distro, will likely include Calf Studio Gear, an extensive collection of LV2 effects and a couple synths. As for ones that run natively on Linux, there's synthv1, samplv1, drumkv1, and padthv1, though I've had trouble getting them working myself.

I've found some good stuff on the Linux Audio Wiki but IDK how up to date most of it is.

There's Bodhi Linux, which is basically Ubuntu+Enlightenment.

Lighter, I think. About on par with LXQt or Trinity (KDE 3).

I loved the default theme, the splash screen, all of the customization options, and how lightweight it was, but it's missing some of the conveniences and polish of GNOME, KDE, or even LXQt and Xfce. Using an independent toolkit meant that none of my apps looked consistent, even after trying my best to find a theme that supported everything, and if I explored the settings beyond a surface level things started looking ancient and clunky.

Definitely underrated, and really impressive for how much they could pack into a desktop targeted at older PCs, but still missing quite a bit.