DNS and IP

I want my website on DOMAIN.com and my teamspeak server on ts.DOMAIN.com. Please explain with as much detail as possible, because I am not that experienced with DNS, (*.example.com) although I am experienced with plain DNS. I have used freedns.afraid.org to point to a public IP. What I want is, to buy a domain with namecheap.com, than add ts.DOMAIN.com to point to my public IP address, and just DOMAIN.com to a website, (not sure what website to use) and my email to be admin@DOMAIN.com.

I have NO IDEA how to do this, and this thread is probably in the wrong spot but I would like as much help as possible.

Thanks in advance.

DNS and IP