BUT! ... A much better option would be to purchase an external PATA/IDE>USB2.0 drive enclosure.
1) OLD (tired) drive is not powered and running 24/7/361 ... Will last many years if only running when needed.
2) Less of a drain (24/7) on your PSU/HEAT/POWER-BILL
3) Portable and cross compatible ... even with Mac and eMusic gear and personal tronix.
4) After transfer of old data to you new systems much larger drive (archive directory) ...
... Then, you can wipe the old drive and use it to transfer files, amongst friends and relatives and can be used to store most important/critical files, off-site (fire/theft).
6) The less complicated your build, the more admin resources will be available to your primary components ... Why should your CPU and controllers have to "baby-sit" that old drive, when it is mostly dormant and forgotten? ... Why should more important devices have to share or wait on that old drive ... just to be polled/acknowledged.
7) Why would you want to slow down your boot sequence, waiting for that old POS to finally spin up and do a slow first seek/init sequence ??? There is this whole test and report routine that occurs at every boot ... old drives just drag you down.
So for all the extra heat and power and working against HVAC and having to listen to it whine until it finally dies because you would never let it rest ... no portability ... no real added space.
fuggetabout-it ... use it in a legacy arcade build, for the basement rec-room. (pong?)
If I build a new computer and place the old drive in it will it automatically look to the old operating system and boot from there? If I then loaded windows seven will the new os set up a duel boot?
I need to know what OS we are talking about here before we proceed.
With XP for example, you put an old drive with OS in a new system. Do a repair install. You would then install windows 7 on a different partition. It will create a boot menu automatically. That all there is to it.