is there any way to hook up a 2nd hard drive, on ubuntu, w/o loosing all my info on my computer

Hello titagula,

Do you know if the drives are IDE drives or SATA drives? Probably IDE, if it is very old. In that case, in order to use both drives at the same time, you will have to connect your second drive to your motherboard. If you're using the same cable to do so, you will have to make sure that one drive is set to Master and the other drive is set to Slave. Else, the motherboard won't recognize the second hard disc.

In order to set an IDE drive to Master or Slave, you will have to change the jumper on the pins located beside where you plug the IDE cable into your harddrive. You might want to look online for pictures. Also there might be a sticker located on top or side of the hard disc explaining the jumper settings.

If you connect the second disc with a second cable, there shouldn't be a problem.

Finally you can use a programme like Clonezilla to copy/clone all your data to the new disc.

I hope that answers your question.

If you can, run update-manager to be synchronous with current version of Ubuntu. It's not mandatory, but could avoid a few problems.
After having set new drive as master, simply copy the old home directory of old disk on new home directory of new disk. It should work.
You will get all your data and also old configurations of software.

Upon looking at my first hard drive, it was on cable select. After research, it seems both of these hard drives should be set to cable select. Does anybody have new instructions using cable select instead?

Have a look in BIOS to see if you can define of two "cable select" hard drive, which one is the first.