HD issue

Well my software understanding is ok, hardware understanding isnt as great, so in reading this post keep in mind Im not someone who opens cases and fiddles so I wont be able to do that stuff. Also sorry for the length.

Anyways, Its parents computer.
-They had a older pc and the mb died,they Gotta new pc and had the techs put in the old hd from the previous computer and a new sata hd in. Considering age, I decided to install windows on the new drive & just kept everything on the old for transfer to the new.
The weird part was during startup I would see the post of our current mb (where you can enter bios), and then a quick flash of what the post looked like on the old mb, followed by a choice between the two xp installations (new hd windows and old hd windows)But everything else ran smoothly.

Lately the comps been running slow thought id do some updates, cleanup ect.,old hd had been quite laggy, and upon reboot, presented with a hal.dll error, and a couple reboots later chkdisk ran and some errors were found on the old HD and then it ran ok.I figured nothing of importance left on the old hd, restarted with the windows cd setup and deleted the windows partition on the old disk.

Thought ill restart see if theres a way to disable the old HD in the bios, and just use the new HD with windows already installed from now on. However upon exit of the windows setup was presented with a warning saying windows setup is not complete. And when I restarted it didnt see the other windows installation anymore either.

So I had 2 windows installations too choose from before, now I cant choose from either and it just asks me to put in a disk too boot. Ive changed the boot priority in the BIOS too the sata drive. Not really sure what else to do.

One other thing too note, thought Id try repairing the windows installation on the new HD in an attempt to get it reckognized but as soon as I tried too (on the new HD) it immediately said "C:"(which is on the old HD) isnt formatted and you need to install windows ect.. It was almost like it needed to be installed on the old HD to work. Which I dont want with the old one failing and everything else installed on the new one. The old HD also always showed up first in the list when looking in the windows setup disk.

So is there any way I can just get it too boot using the windows already installed on the new one.

I wasnt sure with all the specs, but the mb cd says P5N-E SLI and the sata drive is a seagate and i think the old HD was a maxtor.

 

hmm looking at it now maybe it was a lil too lengthy lol, heres condensed:

Gotta new computer. Had harddrive from old computer installed on new pc along with a new sata hard drive. Installed win xp on sata, and when the pc booted up you could choose between both windows installations.

Old hard drive started dieing so threw in winxp cd rebooted and deleted partition with windows on old hard drive leaving windows on new hard drive intact. However now it wont find any windows installations and asks me to install. Ive tried changing the boot order in bios too sata hd but no luck.

MB5N-E SLI
OS:WinXP Pro

 

Ok update, I would have used the edit button but it seems to have disappeared. I removed all the partitions off the old disk, restarted and when i went into windows setup it now identifies the windows partition on the sata drive as C: When i try and install xp (just to see the following msg), it says "To install winxp on the partition you selected setup must write some startup files to the following disk: (old HD) Obviously it cant currently because I deleted the partition.

Is there any way I can avoid this, I personally dont want any ties too the old HD at all incase it comptelely dies. Theres gotta be a way to get all the startup files just running through the sata drive.