This is probably not the best NG to ask your question. If all you want to do is swap an old drive for a new one of the same type and size, you shouldn't have any hardware issues, but assuming you want to keep all the data, operating system, settings, etc. that you currently have, the easiest thing is probably to get a program like Acronis true image, or something similar, to transfer everything from one drive to the other
For that age system, the drive interface has to be IDE (a 40-pin connector on the back). As long as you buy an IDE drive, you should have no problems. It is true that newer drives are designed for faster data transfer speeds, but they are essentially backward-compatible.
As for transferring your data, one poster suggested Acronis True Image. Currently, Acronis has a 15-day FREE trial on their newest version, V.11. There are others out there as well: another freebie is SelfImage, found at:
Lots of folks like Norton Ghost; but, that costs, just as Acronis True Image does is you miss the free trial.
As for the Windows 2000 discs, you might want to check Ebay. Haven't looked for that particular OS, but I have bought both Windows 98 and Windows XP discs off Ebay.
If the new drive is a Western Digital or Maxtor, you can download utilities from their respective websites that will clone the old drive to the new drive. These are just lightweight versions of Acronis Migrate Easy from what I've seen.
Seagate also has a utility to do it. At one point I had to replace hard drives on three machines, and I couldn't get any of the utilities to do it, so I tried the free version of Acronis, and it worked like a charm
Most of these utils only work if the two drives are from the same maker. Bizarrely, for me at least the maxtor utility didn't even replicate to a seagate drive (ie an absolutely identical drive but with an S in the serial number...).
At least the Western Digital version works on any old drive, as long as the new drive is a WD. Last time I had to use the versions of Acronis (old HD were both Seagates) because I had already used Acronis free trials on those machines.
Acronis should work just as well, just thought I'd mention the free, non-trial versions.