So, this is what I have.

I want to get the most drive room on (c) can I "merge" D and Free Space into C. I was told I would have to reformat the whole disk. Thanks guys.

I forgot to say this is on my Windows XP Home OS, not my Vista.

You can move files from "C" to "D" but not programes, to do that you will have to reinstall your progs in "D" then Delete it in "C" There is no need to format your drive unless there are other problems. To move your files open "My Computer" "C" and change size to one side of screen then "My Computer" "D" and set up on other side.
Open the area where you want to take files from, Left click on file, drag to "D" and it will move it.

you got a 128 gig partition almost full and you want to play around with partition tools just to add the 29 gig on D:\ waste of time and frustration go out and buy another harddrive for storage

Sorta agree with caper, there. You have 110GB of stuff on C:... urrrghh... shiver....
If you use a partitioning tool you could add the rest of your hdd [58GB or so] to C: and increase the risk. Get a new hdd, copy off or delete some stuff...[110GB... wow....]. Put the vital stuff in a partition away from XP....
I mean, if I had 110GB on a partition I would not be interfering with it with ANYONE'S partition tool.