With World of Padman was the first test where there is a large difference between Arch and Ubuntu. However, the reason for this is likely that Arch Linux does not use Compiz by default when an accelerated OpenGL driver is available, which is in contrast to Ubuntu. This is simply due to a difference in how each OS is by default. If Arch Linux has Compiz running or Metacity was running instead of Compiz on Ubuntu, we would have likely seen similar numbers.
Nothing to look at with the OpenSSL numbers.
More of the same.
There are no major performance differences between Arch and Ubuntu with the OpenMP-powered GraphicsMagick.