H1B help!!!

Since our lab will move to another university, I will keep registered as student in this university and finish my thesis there, then come back for defence. But this university will not give me scholarship, I have to be hired in the new university in H1B visa. Is it good for me to change from F1 to H1B? If I am in H1B, can I start to apply for GC? How about OPT after my graduation? I know H1B can be for 6 years, will OPT be included in these 6 years? I really appreciate if anybody gan give me advice on these questions? thanks a lot