I just purchased a new computer and have a question on something I am looking to do...

I have an 80gb hard drive currently installed on my pc (it's a 2nd drive). This hard drive is basically a storage drive for all my pictures, music , etc. I would like to remove that drive and install it in the new computer. The hard drive now is one partition. I would like to break it down into 2 Partitions (maybe even 3).

Here are a few questions I'm thinking
1. Can I unplug the HD from the old pc and plug into the new pc, allowing it to work with the new pc (assuming the drive is compatible)???
2. Using the above method, to add partitions would I have to remformat the drive?
3. If I reformat the 2nd hard drive, how do I accomplish that by ONLY formatting that 2nd drive and not messing with the brand new one?
4. Is there a way to add new partitions without reformatting the drive??

Any advice you can give me is greatly appreciated