I have a Sony Vaio with a 120 gig C/D drive. The C drive only has 13 gigs for programs, etc. D is full but I can move stuff over to a 300 gig Maxtor external. The problem is, there's nothing to delete on C and I'm at times under 99 mb of free space. I need to make the partition like 25 gigs or more. How do I do this without having to save everything to disk?
I have a floppy drive with a program called Partition Commander that will let me resize partitions. I would use that and shrink your D: drive (after clearing some stuff off of it, then move the D: partition to the top of the drive stack. Finally, grow the C: partition to fill the newly available space.
If your computer is a part of a domain, make sure you pick the option to not redo the SIDS afterwards or else it will no longer be valid on the domain. Home computers do not need to worry about the SIDS.