f1 to J or F 1 TO H1B ??? PLEASE HELP!!!

[lavan2006]

I am in F 1 visa right now, i am planning to work for 2 years and then want to go for another F1. Do i have to go for H1B or J1????. I would like to know whether converting H1B to F1 is easier or J1 to F1???
Your suggestions will be greatly appreciated!! I have a compaany ready to sponsor me for H1B.
Thanks