Use and to add a second condition to your if statement. In addition to your existing check that the string contains characters, you should also use .isalpha() to make sure that it only contains letters.
Don't forget to keep the colon at the end of the if statement!
print 'Welcome to the Pig Latin Translator!'
original = raw_input("What's your name?")
if len(original) > 0: and original.isalpha():
what am i missing in this one?