I'll cover those for you now.
Off the shelf PCs : warranty invalidated as soon as you OC, so don't do it. I don't mean overclocking them
Media PCs: whay would you want to overclo... oh, hang on, you mean how to go about building one? Yes
Ahh, ok, here's the gen.
Check back soon!
As for server and network stuff... most NAS is now switch on and configure through a webpage just like nearly all routers/gateway modem routers. Tell that to my relatives who get me to set theirs up
Home server = buy Windows Home Server... seriously, it really is very, very good. show me the money and what about Linux Home Servers
What I mean to say is for the majority on here they will know the above, but a lot of people dont, and once you get them hooked then they will visit more
I expect my Hexus T Shirt in the post first thing
Vista PC = Install XP... no, I'm not joking. Save yourself a bunch of arseache and install XP. I don't have an answer for that