Yeah, so long as the key is valid, whether you use a 64-bit or 32-bit install doesn't matter.
Here's the assembly item that you add to the cart.
Larger drives breaking down? It could come from drives with higher capacity having more platters. Drives nowadays have 1-4 platters. Less platters usually means lower power consumption so it is an advantage. It's not something that's usually listed so you have to dig around. I think that the 500GB F3 has one platter and the 1TB has two. I wouldn't be overly concerned about this - I'd be looking more at models with bad reviews or brands with poor reputation - many SSDs have been poor quality but the only outstandingly bad hard drive in recent years is Seagate's 7200.11 series.
Here's some info on hard drive return rates:
Although hard drives are currently priced very high, there's no substitute for backing up your valuable data. No hard drive should be relied upon as absolutely safe.
A great near silent case is the Fractal Design Define R3 - it's around €90 though.
That's a fairly big case; they also have a define mini, which I assume has similar features but you'd need to pair it with a smaller mATX motherboard.
There shouldn't be too much noise from a system like that. The only thing that's there to make noise is the PSU (should be very quiet on low load and should stay quiet for that system), the CPU fan (quiet on low load but would get a bit noisier when doing work) and the case fan. I haven't used this case myself but anandtech said that it was pretty quiet. You could replace the fan later if you weren't satisfied or you can probably connect it to the motherboard to regulate the speed.
If you wanted a quieter CPU fan, the freezer pro 13 is a good choice.
I know that HWV won't install some of the bigger heatsinks in case they damage the motherboard during shipping so you may not want this.