Very Weird Problem! Please help Frustrated!! (W2K)

[sfitr]

When starting my PC in the morning it boots normally without any beeps or error messages and works fine but after some time it starts halting then it almost stops! Then I reboot the machine and when the "detecting IDE DRIVES" come up the primary and secondary slaves are not found. (Its configured autodetect from BIOS) Win2K starts and the D:(which is my cd-rom drive connected as primary slave) disappears. But my DVD drive which is secondary slave is then detected by windows. Then the pc runs ok , no more halts everything works ok except my cd-rom drive which is not found in windows. Also if rebooting or switching on and off the pc several times the "detecting IDE DRIVES" says the same as above! But if I switch it off for a long time and then restart it it boots normally then it starts again; stops and halts. The strange thing is that it doesnt display any error messages or blue screens. Ive been running win2K for many months now without any problems and this thing happened now!
Is this some kind of virus or another kind of error?? NB: I run Norton Anti Virus with autoprotect and live update all the time.

My configuration is:
P4 1,7GHz running Win2K (with all the latest updates)
256 MB RAM
GeForce2 64MB vga card
40GB Quantium Fireball HDD (Primary Master)
LG 52x CD - Rom drive (Primary Slave)
Sony 16x - CD Writer (Secondary Master)
Pioneer Dvd 105 Dvd Rom Drive (Secondary Slave)

[rexregum]

This sounds as if there's a problem with the IDE controller, or rather a compatibility problem between HD and CD-rom. This is a well known problem when connecting a cd-rom to the same controller as the hard drive. Try removing the cd - rom to see if problem goes away. You can also try setting the DVD-rom as primary slave(just switch place with the cd-rom). This because I presume it to be newer than your cd-rom, and certain compatibility issues might not apply to it. If you still experience problems with the cd-rom drive, it might indicate that it is about to fail. Some errors don't show until the unit gets warmed up. Hope this can be of some help:-)