First up, let's take a look at this iconic opening. I hope you know what show it's from!
The peephole frame is, of course, not standard door hardware - its something you'd want to DIY anyway, and make unique do your own door (although this style of frame is available for purchase from a few online stores).
The hardware on the door is quite standard, especially for a New York City apartment. Check out the rim lock - not something you see in many residences, but makes its appearances on quite a few television show doors.
The lock itself is also nothing fancy, but check out the antique pull right below the peephole frame. I'm sure it's these charming details (as well as the rent control) that made Monica stay in that apartment for so long.