As a distrohopper, I've tried to look at all the distros I use with a similar perspective, in case I ever recommended a Linux distro to a family member. Here's a few things from each:
Ubuntu: Ubuntu I would usually say is a great choice, but in my personal experience their new App Center has a lot of issues and has sort of made Ubuntu much more of a hassle to use.
Linux Mint: Overall my experience with Linux Mint has been great, the only problem I think is that it looks old. For people who don't mind, that's fine, but for those who do, it becomes a deal-breaker.
Pop!_OS: Pop is great, except for the fact that they haven't updated since they've been working on Cosmic. I'm sure it's still fine on the security end, but their packages aren't very fresh. Also, if you're planning to dual-boot, Pop doesn't have a dual boot option in the installer, so you'll need to do that manually. So if you're going to give it to a family member with dual boot, I suggest you do the install for them.
Zorin OS: Zorin is extremely old. While I personally have had no issues with this, I've heard people say tat gaming suffers due to the older kernel. I cannot say this has happened for me though. I don't game very much.
Manjaro: For God's sake and the sake of all things holy, stay away from Manjaro. Despite people calling Manjaro 'user friendly', it's not 'beginner friendly' in the slightest. It's 'user friendly' for advanced users. Manjaro also has a history of weird bugs, and they have issues with the AUR because they hold back some packages. It's also based on Arch, so you'll need to mantain it, and you can't just install it once and forget about it.
Fedora: While Fedora is great, it's also got some issues because of some licensing stuff. So if you're going to use Fedora, I'd say go with Ultramarine Linux, because it's just Fedora but with sane defaults.
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