codegolf:
>>> ['%s - %s'%(t[x],x) for x in sorted(t,key=t.get)[::-1]]
['2 - text3', '1 - text1', '0 - text2']
PS. , -, , , :
>>> t={'txt1':1, 'txt2':0, 'txt3':1}
>>> ['%s - %s'%(t[x],x) for x in sorted(t,key=t.get)[::-1]]
['1 - txt3', '1 - txt1', '0 - txt2']
>>> ['%s - %s'%(t[x],x) for x in sorted(t,key=t.get,reverse=True)]
['1 - txt1', '1 - txt3', '0 - txt2']