Hey I plan to re-use my old hard drive, dvd drive and optical drives from my old compaq presario in the system i am building. I notice that they were connected to the motherboard with cables that look different than the ones I see in common modern setups.
Many modern motherboards have at most one IDE (AKA PATA) connection. If possible, try to avoid sharing that between your boot drive and another drive. That will further slow the hard drive down. You can get SATA DVD drives pretty cheap these days so that might be the most economical way to go until you can get a SATA hard drive.
As you will have seen in your old machine, you can connect up to 2 IDE devices per ribbon cable on one IDE port on the mobo. You indicate you have more than 2 in total. Mobo designs used to have two IDE ports commonly, but recent designs sometimes have only 1, or even none. So look carefully at your mobo and see just how many IDE ports you have, and that (well, twice that) will determine how many of your old devices you can re-use.
When you do this, each IDE device must have its jumpers set to either Master or Slave. EACH IDE port MUST have a Master device (preferably connected to the END of the ribbon cable) and may have a second device set to Slave. This does NOT set what device your machine boots from - that is a separate setting in BIOS Setup.