Well, since I recently had to format my 1 TB internal WD HDD (since I wiped out the hdd accidently) I have leant a lot of things that I didn't know about before. Here is a comprehensive list:
1. You would like to format your HDD with GPT instead of MBR. MBR have limitation of only 4 primary partitions in Windows. So you can only create 3 primary partition and one extented partition which can then be divided into multiple logical partitions. If you want to overcome this stupid limitation (born decades ago) you should format the drive with GPT. This will allow you to make virtually any number of primary partitions. Ubuntu plays well with GPT partition, so does Windows 7. But those should be 64 bit OS. A 32 bit OS can't access GPT drives.
2. Primary partition size depends on what OS (or OSes) you want to install. For Ubuntu size can be anywhere between 50 to 100 GB (depending on your usage). For Windows 7 and later (which occupies 10 Gigs only in the installation files), partition should be minimum 100 GB. (You can store Steam games and other big files on another drives).
3. You should use GParted to partition the HDD. GParted can be created as a Live disk or Live bootable USB. Or it can be used by creating a Live Ubunutu USB.
Good luck.
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(I've messed up this one in my system. Now my OS is installed in my 160GB Seagate HDD whereas my MBR resides on the new 500GB WD

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Why not use EasyBCD to recreate or move MBR to any drive you want? I don't know how to but I am pretty sure it can be done.