I have 3 SATA( 74GB raptor, 250GB and 320GB)drives and 2 IDE drives. I recently had problems with the OS which was on the 74GB raptor and seemed to be corrupted. So I added the 320GB and installed the OS again on that one. Since installing the OS on the 320GB I have been having problems and the other day it stopped loading the OS. I decided to re-install the OS onto the 74GB but after erasing the previous partition with the original OS that was on the 74GB. Now when I went to re-install the OS on the 74GB it wouldn't allow me until I disconnected all the drives except for that one. Now the OS is booting up from the 74GB but when I connect the 2 other SATA drives it says that the hal.dll is missing or corrupt. Even I leave them disconnected I can boot up fine. Anyone have any ideas on how to fix this issue. I do have data on the two disconnected SATA drives that I need to keep. Is there anyway to fix the MBR so that it goes directly to the 74GB SATA drive MBR instead of one on the other SATA drives?

Sounds like you have a hardware issue and none of this is related to the master boot record. You need to understand that drive letter enumeration is critical to OS booting. For example if you have a drive with two partitions, one system and one boot [OS is on d:] and then you add a drive to the system that has a primary partition, your OS won't boot. This is because of the rules of drive enumeration. First primary partition per disk is enumerated first. So by adding the drive the OS was now on E: not D:[2nd drive was now D:]. Make sense? First address and solve your hardware configuration issue. Then install the OS with all drives you wish to use active in the system. Golly gee wilerkers everyone. Learn to Internet Search

What if the drives are dynamic? Would that have any affect anything?

Also, I did have all the drives installed the first time I installed the second OS but it wouldn't allow me to install another OS. It would keep saying to create a partition and install the OS on that partition but when I did that it would give me the message again saying that I couldn't install the OS on a partition.

You can't fix a hardware config with software. Good question about dynamic disks - I don't know since I have never made a disk dynamic until after a install. I would suggest you strip the system down to a single drive and install your OS on it with no partitions. Wait for a couple of days to make sure the system is stable. Add one drive back at a time. Be aware that depending on your Bios the standard ide's can be given preferance over the SATA drives which will mess you up on drive enumeration as pointed out previously. You may wish to do your first OS install on a ide drive. Golly gee wilerkers everyone. Learn to Internet Search

I suggest you use Partition Table Doctor to fix mbr or fixboor!