Yes, you have to make sure to get a CPU (processor) that fits in the socket the motherboard uses.
You need IDE (ATA or PATA) hard disks to connect to a motherboard with IDE controller, or SATA hard disks to connect to the SATA connection on a motherboard. Most motherboards come with both so you can choose wich hard disk type to buy, preferably SATA.
IEEE 1394 = FireWire. You can connect things like camera's or external hard disks. Same with USB. USB is more widely used.
FDD is a connection for a floppy disk drive.
TheMajorMMX - Intel P200 MMX @ 225Mhz - V-Tech (PcPartner) Baby-AT mb w/ Intel Triton TX chipset - Nvidia Riva TNT2 M64 w/ 16MB - 256MB M-Tec SDRAM - Still running.....