TomTom has answered this already, but I'll try again and maybe you'll understand from a different point of view.
If you host your own DNS servers, then your registrar doesn't matter much outside of glue records that they'll register on your behalf. This means you have configured
ns2 as authoritative for your zone and registered glue records with them. If you don't know what this means: see #2.
If your registrar hosts DNS for you (which is common for small businesses or personal websites) then you will likely not keep the same DNS records during the transfer - you'll have to check with your host and see if they support zone exports or transfers to your new registrar who will host DNS for you.
If you have to ask this question, you likely fall into bucket #2, but you haven't told us if you self-host your authoritative DNS servers yourself, or if your registrar hosts it for you.
This can be confusing, because people inexperienced with DNS assume that domain registration and DNS hosting are one in the same, when in fact, DNS hosting is usually a complimentary or cheap service offered by registrars. There's no requirement that the two be bundled.