3 problems while formatting my computer

I was trying to format my computer, I had installed the OS of Windows 7 Ultimate x32 bit, and decided to take the opportunity to install a new one, but this time of x64 bits, this was my first time formatting my computer but apparently didnt finish good.

1: When first restart the computer to finish installing the OS, it Said That "The intallation of windows could not be completed. To finish installing Windows, restart the installation"
2: I try to do what it say, but when I try to restart the installation with the OS disk in, I get to the same window (not sure if that's what meant by what I just explained).
3: When I turn on my computer says something like: "select the operating system you want to use", and I get the "Windows 7" option twice.

I just found out according to format the computer i had to delete the partition that was the old OS and create a new one, but I cant get to that window, because as explained in section 2 always get the same message from section 1.

Sorry for my English by the way. Thanks.

That boot menu means you just installed a second windows, apparently not paying attention to what was on the HD already. You need to study a bit more before trying it again.

Follow these steps closely to get a perfect Clean Reinstall which are the same for retail. When you begin the install, delete all partitions then create new one(s) as you wish or just click next and let the installer create one big install partition for you as shown in Steps 6 and 7 of Clean Install Windows 7

Ask back if you have any questions.