Definitely Arthur. It evokes images of knights, castles, dragons, and valour (for me anyway) and I love the historical myths and legends feel it has. Plus it's just a cool and handsome name; adorable for an adventurous title boy, and ages well. My second favourite would be Gregory, mostly because of associations, but a sweet name too.
Wholocked Teen (18) Dreaming of...
✦ Pandora ✦ Demelza ✦ Beatrix / Viatrix ✦ Marigold ✦ Annabeth ✦ Olympia ✦
✧ Caspian ✧ Phoenix ✧ Ptolemy ✧ Horatio ✧ Nikolai ✧ Artemus ✧ Prosper ✧ Ephraim / Zephram ✧
http://www.behindthename.com/pnl/139644