Firmware 1.29 & 80wire IDE Cable

I’m having a computer built by a local business and wanted the Pioneer 111D installed but they couldn’t get them so I ordered the 111D OEM from newegg to install myself. If I want to keep my warranty and upgrade my firmware I need to install 1.29, right? At anytime can I always switch over to one of the unofficial firmwares if I decide I want to?

Also I’ve read that’s it’s important to use a 80wire IDE cable instead of a 40 wire, so is the 80wire the standard in new computers or do I need to tell them to be sure to put it in?

YES for the first part.
Most likely it will come with 80. E.g. Asus mobos come with 80 wire cable included.

I think it has a Intel motherboard. I’ve haven’t installed a burner for quite some time but I just set the Pioneer to Master and the Lite-On Dvd Rom (came with computer) to Slave, then hook up my cables?