Thank you very much for the knowledgeable feedback, this helps alot.
I did some research before posting, but without experience and existing knowledge, sometimes I overlook important bits of info.
That device is called a Power Media Server, and so read the specs: 1.2 GHz CPU, 500MB RAM, SATA I/II, no SATA III, USB2.0, no USB 3.0, no ext. SATA. That is enough to stream video, but it is definitely not state of the art. Using it for backup will probably work. But I would not consider it as real NAS.
My intention is to use it to store:
A) Backups of all my files, especially my programming projects.
B) Backups of my parents' laptops, especially my Dad's Word and Excel files (~10 GB).
C) My purchased DRM-free indie game installers (they won't be installed on the device itself, just stored). <not backups>
D) Alot of MP3 hour-long bible teachings, which I'd probably stream (but could just keep locally). <not backups>
E) A small amount (~15 GB) of music, which I'd stream occasionally (but could just keep locally). <not backups>
F) A small amount (~15 GB) of photographs - family photos, my crummy nature photography, and a lot of downloaded nature photos used for game inspiration.
Both my programming projects and my dad's Word/Excel projects, I want to backup incrementally, so changes are preserved. I usually use Cobian Backup for this kind of thing.
This is to basically say, I won't be using it as if it were just an extension of my computer's local storage. I rather want external harddrives that I can incrementally backup to every day automatically (Cobian Backup handles the scheduling for me), and that I occasionally access from my computer as a Networked Location drive to read some files.
I'm really not looking for a Media Server, I'm looking for external storage on my LAN. Are there better devices of a similar price better-suited for my needs?
On Amazon, I see alot of NAS-devices with the harddrive already in it, but I'd rather be able to access the harddrives and put in my own ones.
Another issue I realized yesterday, is that the particular NAS I chose only supports harddrives in EXT4 file format. Since all the computers are using Windows, shouldn't the attached drives (if using them as Networked Locations) be NTFS or something more Windows-friendly (even though most NAS devices probably run stripped down Linux distros)?
Protection from lighting strikes and power surges can be bought build into power outlet strips.
I have a few power strips about, probably $15 or so apiece. However, I heard that if lightning strikes nearby, power strips won't really protect from that and aren't intended to.
Protection from blackout can be bough as UPS.
But do I need "protection" from blackouts? Is there a risk of damage to the harddrives if the suddenly lose power?
I do not need to access the data during a blackout, so I'm really only concerned about damage that may result from
the blackout. Is a UPS still relevant to me?
The only redundancy is in using RAID (here RAID 1, because you have only 2 bays).
Yes, I was going to use RAID 1, though I'm not experienced with any RAID setup. Is RAID 1 not a good choice?
What you have to consider is whether they should run 24/7.
We have family up all through the night, using computers even after I head to bed. That said, I fully shut down my desktop when I head to bed, and start it up again in the morning when I wake up. I'd probably do the same with the NAS. The family won't access the NAS directly, but I'll schedule backups so their data is invisibly backed up sometime during the day when the NAS is likely to be on.
If so you may think of drives that are made for that purpose (e.g. the WD Red instead of the WD Blue).
Assuming the NAS is on 14 hours a day, 7 days a week, just like my desktop computer, and is really only heavily read from and written to during scheduled backups (I guess 3 or 4 times a day, since I'd probably schedule the backups of the laptops and desktop at different time periods so they all aren't trying to access it at the same time).
When the backups do occur, it won't be hundreds of GB except once a week (during the scheduled 'Full' backups that the incremental backups are relative to).
Would I still want Reds, or would Blues work fine? The Blues are each $15 cheaper (on sale currently), though I'm willing to pay extra if it's worth it. Do the WD Reds really last longer? The warranty is longer (3 years vs 2 years for Blues), so it does seem like WD is willing to put their money behind it.