That was for you and Rshaffer61 as I looked for info. I edited the post as you saw.
I'll go back and do some looking on some things.
Take a look here for the memory. Crucial.com
You have 512mb in there now. It is most likely 2 sticks of 256mb each. We can either go with 2 sticks of 1gb or remove a 256mb and add 1 stick of 1gb.
You do not have to buy at Crucial. I use Tiger Direct. Tiger Direct shows These. You do want the PC3200 because that is what you have in there.
Lets see what Rshaffer61 says on the memory.
As for the hard drive for you. Do you want it for backup of the main system. If so, I would suggest a USB enclosure with the drive inside. That way you do not have to open the case. You just plug it in. It would most likely need to be formatted, but we can help you with that.
As for Chris's computer....
He has a Maxtor 6E040L0 40GB 7.2K 2MB Diamond Max Plus 8 IDE / ATA Hard Drive
There are a couple ways that this can be handled. All require opening the case and hooking and un-hooking the drives.
Once the new drive is attached, then there is software that can be used to clone the drive (puts the entire contents of the old drive on the new drive).
If Chris/you have the original software, we can also reformat and load a new OS on the drive.