This is a very easy task to accomplish. Ubuntu's installer is configured to put the boot loader by default on the hard drive where you install Ubuntu. The boot loader is also configured to find other boot loaders and include them in the menu. You only have to make sure that the hard drive where Ubuntu is installed on is the first hard drive in the boot order.
Doing it this way will not touch the Windows boot loader, which means you could remove the Ubuntu drive and still can boot Windows. Installing the Ubuntu boot loader to the Windows disk of course will break this and is not recommended.
You can of course use tools like the mentioned boot-repair. But if you want to get things right I'd recommend reading the manpages, like the one for grub-install, and the Ubuntu and sometimes Arch Linux wiki pages.
The grub-os-prober, responsible for making Dual Boot configurations easy, can also be disabled, so that only Ubuntu related menu entries will be generated when running
uptade-grub from terminal. Some other Linux distributions ship default configurations like these.