This is right in my wheelhouse. I've been Ripping Tunes since the technology was first developed, and have thousands and thousands of Albums converted to various File Formats. (For example I have over 4000 Albums in FLAC format on this PC. 1.6 TB consisting of over 60,000 tunes. I strongly recommend FLAC to anyone just starting out.) I also have a hobby of building and repairing Computers (Windows PCs only - no Apple) including some Laptops for Close Friends and Family.
My suggestion is to go for an LG if you can afford it, but Dell is about the same reliability, as is HP, at the same price point. You really do get what you pay for these days. All OEMs are using components from everyone else. If you've ever dismantled a Laptop it's quite obvious. Dell & HP don't really manufacture anything. There are assemblers of the efforts of others. They source motherboards, Hard & Optical Drives, Power Supplies, Screens, RAM, etc., from various OEMS. They just design the package. I doubt they make their own plastic / metal cases but I have no documentation on that. (I'm just speculating.)
As for storage, as a NAS seems undesirable - which I understand as I've avoided them as well => I'd go for two USB-3 portable Hard Drives. Everything would be ripped to one and then copied to the Back-up. There is far too much effort required to re-rip a whole CD Library if you lose it when a drive fails. And they all fail - it's just a matter of when. I tend to buy Seagate or Western Digital (WD). Don’t bother with the software that comes with your external hard drive. Buy 2 drives as large as you can, as you'll be amazed how fast you'll fill it up.
I hope this is helpful.