Well since no one else has mentioned it, let me cast my vote for the Lihue area. We have been to Kauai twice, and found the access to both North Side and Poipu and Canyon areas, excellent from here, as well as a fair amount to do, right in the Lihue area. We really liked the Kauai Marriott, and it's beach, though the water wasn't always crystal clear because of the traffic in the nearby harbor, but certainly not bad to spend a day or two between trips to outer areas. We also checked out some new condos in the Waipouli (a little north Lihue) area that looked very nice, though I believe the surf may be stronger in that area.
Cindi