It may help if you partition the drive first. You can't install it without an appropriate partition. There is also a slim chance that you have an unsupported chipset.
No, the RAM will be automatically detected when installed and requires no actual software updates or user input to install it.
No it does not. As long as the motherboard has the proper connectors for the hard drive you are installing, IDE or SATA, you will not have to replace it. If the connectors are different, then return the hard drive and get one with the proper connection type.
operating system
the hard drive should be set to master...
I would suggest installing windows on one hard drive, then installing ubuntu on the same hard drive. Use the other hard drive for the backups (partition it).
Installing the program to your hard drive
Assuming that the only other drive you have on your system is your hard drive, then a hard drive failure could be why it is not being detected. The hard drive could also not be installed correctly, but unless you have taken it out or changed the settings in CMOS, then this is unlikely.
yes all hard drives must be reformatted before installing an operating system.
without a hard drive your PC wouldn't work at all. so you must have a hard drive, whether its internal or external...
yes you do.
Defragging the hard drive
You normaly only need a srew driver