H1B stamping to H4 Stamping and back to H1B status


I am on H1B and wokring in US. My wife is in India, she got her H1B approved and stamped. Currently there is no client openings available for her to come to US. Can you please give your feedback on below questions.

  1. Is it OK to come to US on H1B and does not work?

  2. What will happen to her H1B if we go for H4 stamping now?

  3. If we get her H4 stamping done, how difficult is the process to change back to H1B (which is already stamped)?

Please suggest a safe and legal way to bring my wife to US with out affecting the H1B.

Thanks in advance