Super noob help with name servers...

Okay, I currently host with the planet, and a lot was set up and stuff I did, I did almost 5 years ago and therefore can't remember. But I'm going to host from home using webmin and virtualmin. But I'm really confused for some reason. I had a domain name, and at the registrar I set up two name servers, namely ns1.example.com and so on using a couple of IP addresses supplied to me by my server at the planet. On whm, I set up two name servers according to those ip addresses. Actually I probably did that first. Anyway, does one "have" to set up their own name servers in order to host websites, or can they use the ones supplied by the registrar? And if you do, I can't for the life of me figure out how to establish those name servers on webmin, or virtualmin for that matter, whichever is needed to do it. Anyway, I hope this isn't too noob and thanks for the help!