Congratulations !
Don't worry too much about the cables.
A few years ago, harddisks (and cd/dvd players) were connected to the motherboard via "PATA-cables". Those were those wide ribbon-like cables. They could block a lot of the airflow in your case. Nowadays all HDDs, SSDs, dvd players use SATA. Those small red cables. There is much less risk in blocking airflow through your case.
I used to be worried about static too. I think it's not that bad. Because nobody uses those wristbands anymore. Just try to not touch the metal on your components more than necessary.
Good luck installing Windows. That sometimes causes more frustation than building the hardware.
