Would like to install Ubuntu on secondary hard drive within my computer

Okay, so here's the story. I am trying to install Ubuntu 13.04. I currently have a 2TB drive in my computer where Windows 7 boots from, and a secondary 500GB drive that also has a bootable installation of Windows 7, because the version on the 2TB is a clone of what was on the 500.. I do not need any information on the 500 as I already have it moved over to the 2TB. What I want is to completely reformat the 500 so that it has about 300GB for NTFS and the rest for Ubuntu. However, I can't seem to find a straightfoward way to do that in the Ubuntu installer. If I click on "Install Ubuntu alongside them," it does not give me the option to select my 500GB drive, only my 2TB. I do NOT want any linux partitions on my 2TB drive. I do not want to click, "Erase disc and install Ubuntu" for obvious reasons. Finally, clicking "something else" brings up a menu that is quite confusing. I can kind of figure out how to use it, but it's not as straightfoward as I'd like.. Further, I know that Ubuntu requires a SWAP partition, but I do not know how much, or even how, to allocate that with the stupid dropdown menus it gives me.

So, to get to the point.. What is the easiest, safest way to do what I want to do? That is, allocate approximately 200G for Ubuntu on my 500G drive, and be able to choose between Windows 7 on my 2TB drive and Ubuntu at startup - all, of coarse, without touching the 2TB drive at all.

Thanks!

You're right. Choosing Something else will allow you to accomplish your task. Now you mentioned that you want to create a partition of 200GB for Ubuntu. So you would create a partition of 200GB, and choose a mount point of / and create a swap file, twice the amount of RAM.

The images below are for illustration purposes, your actual case might be different.

Click on the + sign to create a partition.

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