Hi, I'm new here, so Thanks! for any and all help

K, this will be a long explanation. I'm working on an EMachine S1940, AMD Athlon XP 1900+, that originally had Win Xp Home on it. My friends sister was in this computer, and (I think) deleted the wrong thing. Methinks this puter was having problems, maybe many, before I ever laid eyes on it. So, she gave it to me, to see if I could fix it. Now, I don't have the restore disks that came with, she can't find them, but I do have my own Win 98SE Full Edition. So, I'm trying to load in the 98, and I cannot get the computer to recognize the cdrom, so it will start the set up. (there is a cdr in here) I have wiped the hd, reformatted, even reset the mbr, but nothing works. (yes, I did do your step by step instructions on installing win98) Now my sister, "her geekness" has helped every step of the way, but even she is stumped! From everythng we have found online, in forums, and elsewhere, all we can figure out is that either the cdr is dying, and I need to get another one,(it does light up, and I can hear it turning) I may just need to clean it, or the Win 98se does not have the correct drivers for the more advanced hardware. I have also gone into the DOS, and reset the boot order, to start with the floppy first, then the cd rom, then the HD, but nothing has worked so far. I can get the puter to reformat, but when it comes time to load the windows, the message I keep getting, is that CDR101 device not ready. Now we did do our homework on this message, that's how I know that it may be a hardware issue. I have gone inside, checked all connections, removed the memory stick, and reseated it, even removed the battery, (by the way, I took the battery out for over an hour, and the puter still had the partition in that was there when i removed it, my sister said that was very strange) When I get the A prompt, if I type in a C prompt, it will show one, but when i type in setup, i either get the message that C is not a valid drive, then have tried D prompt, get the same message, have even gone thru every letter of the alphabet to try to find one that will work. Also there are times I get the message: Windows 98 cannot find set up files" Also, most of my messages tell me " bad command or file name" Anyone have any other ideas? My sister says we may have to do switches next, then she makes this "sound" in her throat, hehehehe I guess we are just looking for another brain here, to see somethng we may be missing. Thanks in advance for all of you're help, this is me looking at this computer now