Can I skip the first two years of ROTC because I am prior Navy?

The general rule is that basic training exempts you from the first two years of ROTC. You have completed basic training, albeit not Army basic training, so you should be ok. Worst case you could request to go to ROTC Summer Camp which also covers your first two years. I've seen guys do their masters while in ROTC, although that's obviously not the norm and was during the early years if GWOT when the Army needed people more than now. Your best bet would be to talk to the Professor of Military Science (PMS) at whatever university you want to attend and get his advice.

PO3 (Join to see), the best person that can help you in this instance is the Recruiting Operations Officer (ROO) at the ROTC of the university you are interested in. Go to the university's ROTC page or department and you'll find a point of contact Good luck!

A Professor of Military Science can award credit for the ROTC basic course (1st 2 years of classes) based on any Military Basic Training. So Navy recruit training could work. However. for a Masters program, you have 2 years to complete that and the last 2 years of ROTC. Also, the medical requirements for contracting with ROTC are the same for enlisting in the Army. So if you are working on a waiver, you would not be able to contract with ROTC until that is approved. I would also recommend you look at doing ROTC Basic Camp. While Navy boot camp can count, the skills you need as a cadet and then an officer are completely different. So Basic Camp would be a good way to get familiar with being a cadet.