How do I put 2 images in one blob field?

you don't, would be my guess

i want to show that a hotel is a 1 star or 5 star

i would use a TINYINT field for that and store an integer from 1 to 5

then, in your scripting language (asp, php, coldfusion, what have you) i would translate that value into the number of star images, which would be retrieved from the web server's file system

storing images in mysql is generally not a good idea