It all depends on what your NAS is used for, and how you use it. Do you have static mappings from multiple machines that could get some corrupt data problems, if you shut the NAS down? There is a way to schedule a sleep timer in the console. If you use that, be sure any open files on it- are closed.
IDK what was up with the daylight time thing. There's settings for that too in the console. My terastation sets the time from the default time server buffalo uses for that. Linkstations can do the same thing.
Leaving the drives on and spinning should be ok, but it will kick up the power on hours. I leave mine on that way 24/7, but I also rotate my drives out in upgrade periodically, which also helps avoid most drive failures. And my useage is not super heavy either.
WD red drives are great for buffalo units. But I would not scan them each week, unless there is a need to. Like when you start seeing some data access problems or corruption problems.
I've had an array of 4 of those reds running RAID 0 in a TS3400 for almost two years now. Never any problems. I don't weekly scan, but I do backup and I backup pretty often.
Since raid isn't backup anyway:
I'd be more concerned with making a good weekly backup (or even daily if it is critical stuff) and getting that done, vs a weekly raid scan.
According to the manual for your model, raid scanning should be done for Raid 1. I use Raid 0 and raid scanning isn't supported for that mode. Given the time it takes to do the scan and the amount of wear on the disks for it, it's probably best to do it during off hours on a weekend, once per month, or every 90 days. Or after the power failed, or something else that deemed it necessary.
You could run a daily error check. I would be concerned about open files and getting data corruption, because running that error check will kill any ongoing file activity of open files or any running backups. I run an error check about once a month or so, or when windows has trouble accessing things on the NAS, etc.