The minimum system requirements for installing Windows 7 are the availability of Mac OS X v10.6 Snow Leopard or later, along with Boot Camp 3.1. You will also need an optical drive and a Windows 7 full-installation disc.
A 32-bit version of Windows 7 will work with an iMac or MacBook Pro launched in 2007 or later, and any Intel-based Mac Pro, MacBook, or Mac mini. The 64-bit version of Windows 7 will work with Mac Pro or MacBook Pro launched in 2008 or later, and any iMac or MacBook, introduced in 2009 or later.
If you do not have Boot Camp 3.1, go to the Apple menu and select Software Update, to get its latest version. Back up all your Mac data before beginning installation.
To begin with, Boot Camp will help you create a partition for Windows, as well as start the Windows installer.
Log into an administrator account and quit any open application. Log out other users on the computer. Go to Software Update and install all the available updates.
Go to Utilities folder in Applications, and open the Boot Camp Assistant. It will walk you through the entire process with the help of prompts. Boot Camp will help you select the size of your Windows partition and create a partition of the internal disc for Windows, without erasing existing data. Select NTFS format as it's the most reliable option.
Do not delete any partition or create a new partition. Select only "Disk 0 Partition 3 BOOTCAMP" when installing. Then select 'Drive Options (advanced)' and click 'Format' and OK. Once done, click Next and the Windows partition will be formatted using NTFS file system.
In Boot Camp, select 'Start the Windows installer'.
Now, insert your installation disc and click on Start Installation in Boot Camp. You will find your computer starting from the Windows installation disc.
You need to follow the instructions, and select custom installation.
After the Windows software is installed on your Mac, it will restart automatically. It will use Windows to start up. However, this does not complete your installation process.
You need to install the Boot Camp drivers for Windows. Eject the installation disc for Windows 7 and insert the Mac OS X disc. You will be prompted with instructions that you need to follow. Your computer will restart and you need to follow the instructions of the Found New Hardware Wizard or any other wizard that appears, and update the software drivers.
Once Windows and Boot Camp drivers are installed, you can start using Windows 7. When your computer starts, it will load in dual boot mode and let you choose between Mac OS X or Windows 7. Mission accomplished.