The hostname is of no concern whatsoever. Hostname is a local issue, and you are looking at an internet issue to get mail to the box. Your computer can be localhost.localdomain (the default), and as long as the DNS is set to direct email to your IP address, it will receive it regardless of the hostname.
How is this computer connected to the internet? Is it through a cable modem with DHCP, through a DSL with DHCP, or does it have a static address?
You need to create an A record for mail.compunerdedev.com in Zone edit, and the A record should point to the real world IP of your mail server. Then the MX in zone edit should point to mail.compunerdedev.com.
Other issues to consider - you probably don't have a static real world address at your place. Anytime your connection changes its address, you would need to update the zone edit to the new address. Doing that can be a pain, and if you are in that situation, you would probably want to use a dynamic dns (dyndns) service, to always keep track of your real world IP, and report changes. If that is the case, there is a work around, basically using the CNAME instead of an A record for mail.compunerdedev.com, and pointing the CNAME at your dyndns name.
If you have a router or firewall, you'll need to configure them to pass traffic at port 25 (SMTP) to this computer in question. Also, to read the mail, you'll either want 110 open for POP3, or 143 for IMAP. It can also allow both, if you have services running on both. If the computer has a private IP address (192.168, 172., 10.) then you have to port forward from the router/firewall to this address, and you should make certain that private address is either static, or that the DHCP by the router has the MAC address of the machine, so it always gets the same address.
Once you have the DNS resolved, pointing the machines at it either by its LAN address or pointing them at mail.compunerdedev.com will work fine.