Trouble installing 64-bit Windows 7, but it was my fault, kinda

I installed 32-bit Windows 7 on a Frankenstein machine that I built myself using old components that I had lying around (except for the CPU and 2GB of memory), and installation was a snap. First, I had 32-bit Windows XP installed on the machine, because I had to make sure that the machine was runnable. Next, I extracted (using 7-zip) all files from the Windows 7 ISO file onto a portable drive. Ran setup.exe from the drive and everything went smooth on the first try! It found drivers for every device I'd hooked up, except for a remote printer. I think I actually like Windows 7.

Then, on a different (and new!) machine, I tried to install 64-bit Win 7 and it was driving me crazy. First, since the machine had 32-bit XP, I couldn't use the trick of extracting files from the ISO and running setup--under Windows XP you can't run a 64-bit executable (setup.exe) from a 32-bit OS (XP). So, I had to burn a bootable DVD (can't use a CD, the ISO file is 3GB in size). When I tried to boot using the DVD, the setup program kept asking a CD/DVD driver file! Google came to the rescue and I found out that the reason that I got the error was probably because my ISO file was corrupt. I checked, and it was true: instead of a 3GB file, my ISO was about 1.3GB in size. Pretty stupid of the installation program to not realize that it was working with a corrupt disk image, if you ask me. Anyway, I re-downloaded the full image from MSDN AA. Then, I tried to use the "ISO Recorder" program recommended by Microsoft for burning ISO files onto disks. But that doesn't burn DVDs on Windows XP. Yecch! Had to use Roxio to burn the installation disk. And then the installation took like an hour--at least it felt like it. But the end result has been great. The machine has been running smooth and Windows Performance Index (or whatever it is called) pegged the machine at a decent 5.3.