The Namecoin software is console-only, it is based on bitcoind. Running it is similar to running another copy of Bitcoin, it has it's own wallet and blockchain.
If you don't need Namecoins and only want to sell them (you don't want a Namecoin domain name etc), then you likely just want to send them to an exchange and use that like an online wallet.
https://exchange.bitparking.com is the oldest and largest for NMC<->BTC, but as the previous poster alluded to, they have one-time-use deposit addresses, so you can't automate multiple pool withdrawls.
http://ozco.in pool has an option to "enable automatic Namecoin exchange into Bitcoin".