Quick question

[Eagles18]

Hi,I want to install the newest version of Ubuntu,but I have a question.I want to install it in my C:/ drive,which is were all my files are(including my OS).Even though it asks me how much memory I want to use for Ubuntu,I'm not sure if it will overwrite my current OS(Windows Vista).Will it?
Thanks in advance ):P

[lisati]

Before you begin anything major (and installing an operating system is something major) it's a good idea to make a backup of your important data,

How do you plan to install Ubuntu? Are you starting your computer form the CD or are you starting the CD within Windows? (This can affect what advice we give)

[Eagles18]

I'm starting it within windows.BTW,thanks for the quick response