The start of a game in pygame, blitting images to the screen
As noted in the beginners guide, you should convert your image right after loading it. So instead of

tableTex = pygame.transform.scale(pygame.image.load('./Sources/Table.png'), (270, 240))


Do 

tableTex = pygame.transform.scale(pygame.image.load('./Sources/Table.png').convert(), (270, 240))


As noted in the guide linked above, this can lead to a speed-up of about a factor 6. The reason is:


  The 'format' that convert() refers to isn't the file format (ie PNG,
  JPEG, GIF), it's what's called the 'pixel format'. This refers to the
  particular way that a surface records individual colors in a specific
  pixel. If the surface format isn't the same as the display format, SDL [what pygame uses underneath]
  will have to convert it on-the-fly for every blit -- a fairly
  time-consuming process. Don't worry too much about the explanation;
  just note that convert() is necessary if you want to get any kind of
  speed out of your blits.