I would like to inject some reality, and add yet another option. This is your approx. timeline for the next 2 years :
8 weeks of boot camp
6-16 weeks of NF "A" school (not sure on lengths any more, sorry)
6 months NNPS
6 months NPTU
Congratulations, now your a NUKE!, now for the next year:
get to your first ship, Welcome aboard, your Dinq, get hot NUB
now you have to qualify all of your in rate and dolphin quals, assuming you are an ET on a 688
RT, AEA, PVO, Phonetalker, BEQ, RO, SRO, SEO
Now your career is approx half over, and this is where I would like to put in a plug for another option. the Navy has a program called NCPACE, which you can use to take college courses for free (plus the cost of books, about $200 per class) while serving shipboard. If you are smart, manage your time well, and have the support of your command, you can conceivably complete a degree over the next 3 years. There are several key factors to making this work: 1) you have to not be seen as a dirtbag by your crew. i.e. qualify early, know your stuff, don't get in trouble. 2)realise that the needs of the division/dept/ship come before everything else. 3)have to be willing to put in the time/effort on your own time after working hours or between watches i.e. when all your buddies are out partying or burning a flick, you gotta be hitting the books. You can also use what is called TA, Tuition Assistance, similar to NCPACE. I have seen a few people actually do this, but it is pretty rare. However between NCPACE, TA, and CLEP/DANTES Exams to test out of stuff, it can be done.
Good luck, and welcome to the Navy, it's gonna be a helluva ride
-Matt