Well, let me get some more info from you to see what the best way to do it would be.
1. When you click on "my computer" how many drive letters (i.e. partitions) do you have? I assume the C: drive is from the 4 GB hard drive and you must have at least one more letter for the 40GB drive. Don't include floppy disk or cd drive letters. We are only interested in hard drive letters.
2. How much total space and free space does each letter have?
In terms of creating partitions, it is very easy if you have a program that does it all for you, but we'll get to that later.
And as far as "is it worth it to do all is or would you cause more harm than anything else" - well, it is worth it if you plan on using that computer for a while and windows is running out of space. Everything should work out fine, but you always will have the small possibility that something you wanted to keep gets erased. I have done this type of thing many many times and only once did I have problems - and like I mentioned earlier, that was likely due to the fact that I was dealing with a defective harddrive.
Now, if out of your 44GB total space, you are close to running out of space anyway, then I recommend buying a new harddrive and saying bye-bye to the little 4GB guy.
What would be ideal in your case with what you have would be the following:
1. Use the 4 GB drive as storage space (it's its own partition)
2. Have 2 partitions on the 40GB drive, one of which would be about 10 GB and would have windows installed on it. This partition would be your new C drive. The other partition (about 30GB) would be used as storage space.
3. Ideally, we would set it up so that folders like "my documents, my pictures, my favorites, my music, etc..." would be on the 30GB partition. That way in the future, you could always make changes to the C drive and even reinstall windows if you needed to, and your important data would be safe on the other partition. By default, windows places all that on the C drive, but that can be changed.
Ok, enough rambling. Let me know the answer to those first questions and well go from there.