Python version 2.6 required, which was not found in the registry
I realize this question is a year old - but I thought I would contribute one additional bit of info in case anyone else is Googling for this answer.
The issue only crops up on Win7 64-bit when you install Python "for all users". If you install it "for just me", you should not receive these errors. It seems that a lot of installers only look under HKEY_CURRENT_USER for the required registry settings, and not under HKEY_LOCAL_MACHINE. The page linked by APC gives details on how to manually copy the settings to HKEY_CURRENT_USER.
Or here's the PowerShell command to do this: cp -rec HKLM:\SOFTWARE\Python\ HKCU:\SOFTWARE
Can't download any python Windows modules and install. I wanted to experiment with scrapy framework and stackless but unable to install due to error "Python version 2.6 required, which was not found in the registry". 
Trying to install it to
Windows 7, 64 bit machine