As long as sdc has no data you care about, use gparted and partition it this way.

I have BIOS but use gpt. I have created my gpt partitions with gparted. Under device, create partition table, advanced, choose gpt not the default msdos (MBR) partitioning.
That erases everything.


For the Total space you want for Ubuntu:
Ubuntu's standard install is just / (root) & swap, but it is better to add another partition for /home if allocating over 30GB.:
Only if gpt - all partitions in gpt are primary:
gpt: 250 MB efi FAT32 (for UEFI boot or future use for UEFI, you only can have one per drive, so if already existing do not attempt another)
gpt: 1 MB bios_grub no format (for BIOS boot not required for UEFI)
gpt or MBR(msdos)
Ubuntu partitions - smaller root only where hard drive space is limited.
If total space less than about 30GB just use / not separate /home or standard install.
1. 10-25 GB Mountpoint / primary or logical beginning ext4(or ext3)
2. all but 2 GB Mountpoint /home logical beginning ext4(or ext3)
3. 2 GB Mountpoint swap logical

Depending on how much memory you have you may not absolutely need swap but having some is still recommended. I do not hibernate (boots fast enough for me) but if hibernating then you need swap equal to RAM in GiB not GB. And if dual booting with windows a shared NTFS partition is also recommended. But you usually cannot create that as part of the install, just leave some space. Or partition in advance (recommended).
One advantage of partitioning in advance is that the installer will use the swap space to speed up the install. Thanks Herman for the tip.
https://help.ubuntu.com/community/DiskSpace
http://ubuntuforums.org/showthread.php?t=2021534

Instead of a separate /home I actually use two data partitions. One is NTFS for data I shared with my XP and the other is ext3 (I would use ext4 now) for all my new data. Then I keep /home inside my 25GB root partition and link all my data back into /home.