Giggs has no managerial experience, it'd be a massive risk for Man Utd to let him become manager of the 1st team. I don't think Mourinho will be sacked yet any way.
maybe yes he has no managerial experience, but look at what zidane have done to Real Madrid, is he have a managerial experience? and he give a 11th champions league trophy to Real Madrid. How if Ryan Giggs become another Zinadine Zidane?
You can't compare Real Madrid with Manchester United, dude. It's really different, because Real Madrid is a big team that have solid players even chance with other manager. In the other hand, Man United performance is really unpredictable.