Missing ntfs.sys, isapnp.sys, pci.sys etc. problems

Hello I have a desktop PC with Windows XP PRO that I just fixed after a few years of it not working, it would power on but wouldn't display anything and would also not beep on start up. I put in a new video card and changed the CMOS battery. Computer turns on and displays on a monitor. My problem is I get to "choose a mode to have windows start in" and it doesn't matter what mode I choose I always get the same couple of results. Missing ntfs.sys file, missing isapnp.sys, missing pci.sys and that I need to insert the original setup CD-ROM to possibly repair and select 'r' at the first screen to start repair. I try to do this and every single time I never even can get into the start repair screen. I have changed the boot order multiple times. Have tried almost every combination.

Does anyone have any ideas of what could possibly be going on? If you have any questions for me that could help you help me please let me hear them!! Thank you in advance.
@Semikiler: also, please note that if your attempt a repair install that the cd you perform the repair with must be the same service pack as what is on the installation.

i.e. cd is sp2 then the os must be at sp2
Okay, well I have both good and bad news. I took my hard drive with XP pro on it and hooked it up to a working computer. I was able to reformat my drive using the NTSF quick format which turned out just fine in my friends computer. Windows XP pro SP2 booted up perfectly. Now here is where I ran into some trouble. I figured that since windows started up just fine in my friends computer that it ought to work in mine, the computer that the hard drive originally came from. I hook everything up correctly and it looks like it is going to start up just fine and I will finally have my beloved computer back after a few years of being decommissioned ... until I reach this screen. "Windows could not start because of an error in the software. Please report this problem as : load needed DLLs for kernal. Please contact your support person to report this problem."

After I had this issue I decided to remove the hard drive from my computer and place it back into the working PC that installed XP Pro to see if it would start up correctly. I bet you could never guess what happened. The Microsoft Windows XP PRO OS booted up just fine with no issues what so ever. Now at this point in time, I am wondering if it could be a still a hardware issue, or could it even be I need to flash the BIOs because the CMOS battery in my motherboard was dead for quite some time? Does anyone else have any ideas of what to try? Thank you!!
replace the battery, a cmos battery will hold info while the pc is off, it it has been off for a while then yes I would say it is dead, after replacement, go into bios and restore to default settings, and see if it will boot now.