We were in Savanakhet for 29hrs and I enjoyed the French food at both "Dao Savan Restaurant" and "Chef Boon". We did stay at "Dao Savan Resort" what is a bit out of the way and overprices (but wifes preference). Later in the day I saw that there is an brand new hotel, just in front of the ferry terminal (for Thai & Lao). It is a good looking hotel in the price range of 26us$ to 100us$. No swimming pool and the restaurant is not finished yet. Private car parking in front of the hotel.
We did take the bus from Mukdahan bus-station that goes over the bridge and goes to Savanakhet bus-station. It costs 50thb pp. The bus will drop you first off at the Thai immigration to leave Thailand and pick you up again just after the Thai immigration. Then the bus will ride over the bride and drop you off just before the Lao immigration. Visa on arrival, pay in us$ is much cheaper (saved me 500thb). Then the bus will pick you up just after the Lao immigration and rides to Savanakhet bus-station. That is still about 2km out of the city centre. From there you have to take an Tuk-Tuk.