what do you mean you have not renewed passport for 5 years. does that mean your passport was expired 5 years ago and you have not renewed until yet? in general you have to renew your passport at least 6 months before it expires. it is to be on safe side. i renewed my passport 4 months before expiry date. i did exactly what instruction in embassy form said. I got back my new passport within 2 weeks. go to this site http://www.nepalembassyusa.org/passport.php download the form, fill it up, and do exactly what it said.

if your passport is already expired then i have no idea how to proceed. may be someone will suggest who went through same situation.