Yes, you can. You can also walk to Hollywood Studios, but it's a little longer walk. They have boats, but they are pretty slow because they also stop at the BW and the Swan & Dolphin. If you stay there the PH tickets are so worth it because you can hop into Epcot every night for dinner.
I've stayed there for a conference and at the Beach Club for fun. The theming at Yacht Club is the most "adult" of any Deluxe at Disney. It shares all the amentities of the Beach Club, so the same pool, gym, restaurants, etc. I highly recommend the Crews Cup Lounge (outside the Steakhouse) for an easy dinner or drinks. The only downside is that there really isn't a Quickservice restaurant that's convenient. You pretty much have to walk all the way to the Beach Club Marketplace.
We've stayed at the Beach Club, which is their sister resort - like PP said, they share amenities, including the awesome pool. I'd stay at the Yacht in a heart beat - I love the theme, the pool, the walk to epcot. I totally agree on getting park hoppers, too.