We had a brief 2 night stay at Ryuguden. Given a message the day before, they provided us free shuttle bus rides to-and-from Odawara Station to the fairly remote spot it's located next to the lake. Once we arrived, we were warmly greeted by the reception and our receptionist at the time spoke good-enough English for us to check-in without problem. Then we were given the keys and shown to our room.
The room itself is spacious, plenty of space to sleep, move around, and lounge all at once. Of course, the highlight is the view in front of the window, the view of the lake and Mt. Fuji. It's a great view. As for the (comfortable) futons, the staff laid them out during dinner and then put them away during breakfast.
As for food, it's a chef's course for dinner. A manner of meats, vegetables, seafood, Schrodinger's tofu (the number of times a cube wasn't tofu...). It was delicious. For breakfast, a full spread. Also delicious. Each room gets assigned the same table in the dinner room for the length of their stay.
And then the onsen. The indoor one in the annex building is serviceable. But the view from the indoor/outdoor one in the main building (provided free of charge to guests) is spectacular. There is no better way to relax then to soak and watch Mt. Fuji in the crisp outside air. We onsened twice a day.
As for the location itself, many of Hakone's attractions are at most a 20-min walk. Very convenient.
I recommend!