Greetings...
Well, a friend of mine and I both agree that travelling should be difficult, and tiring. After all, the word 'travail' and 'travailling' has evolved into the word 'travelling' to mean a slightly, and then eventually, totally different meaning. As such, we have houserules where we start giving subdual damage for travelling. If you push beyond the 8 hours, you start taking subdual damage, dependant upon the terrain and conditions.
But, with that said. How do you make travelling interesting? Well, first, I like to emphasize on things that would be relevant to the players. Rangers and Druids, I would have them roll for spot/awarness checks and tell them they notice tracks of various potientally dangerous creatures. If they tell me that they are looking for food, I also mention animals that might be good to hunt for dinner.
If the players like to roleplay, or things get boring while they are roleplaying a particular situation. Such as, the Wizard says he's going to memorize his spells, and the Fighter is off doing his morning sword practice... Any characters, such as Wizards or Clerics and especially Bards who take Knowledge (History) I will throw in little tidbits about the locals, just off the top of my head: "This field is probably where the battle of Gundark was fought. Where the nearby town ambushed and fought a large number of orcs, out-numbering them 3 to 1. It's become quite famous in local lore."
For the ship travelling, you have a number of NPCs that are exposed to the players for at least a fortnight. I would allow the players to explore roleplaying situations with them. Some sailors talk about phantom ships, lost treasures, the wonderous things they've seen, pirates and battles. Perhaps start the characters by overhearing a couple of sailors talk about 'what strange folk are aboard with us'. Or they talk about seeing a phantom ship, or hope they won't see it this voyage.
Also giving you chances to either foreshadow upcoming adventures/events in the current campaign, or plot-hooks for future adventures. Allow the players to also interact with the NPCs to gamble, or improve skills, or if they go out their way to roleplay, and make things a little more interesting, rewarding them. Since the wizard has gone out of their way to talk with the crew, one of the crew gives them a scroll that they picked up somewhere that they have no use for.
Generally though, I don't get a party of players who are interested in roleplaying the travelling and resting for the evening at the local inn too often. So, as for the travel itself, if nothing really important happens, I normally just glance over the whole trip. But sometimes I get the occational player who wants to roleplay more than the average player, and I generally reward them, and the other players if they start roleplaying more. I feel that roleplaying shouldn't be a reward totally onto itself. It should get XP just like combat and problem-solving. So, I give little bonuses here and there.