No..your computer will explode and burn your home..
Damn, I better take that IDE drive out of my MCE system and just leave the 2 sata ones. I would hate to have it blow up while I am at work.
Yes you can. The only issue you'll have is telling the bios which to boot from. Plug them in, then go to the bios and select which one you want as the boot drive. The last time I had an IDE drive I plugged it in and the bios assumed I wanted to use it as my boot drive. I told it to continue to use my SATA drive and all was well.