There are a total of 18 Value studios, 10 are lockoffs and 8 are dedicated studios. Your confirmation will state whether you have a lockoff or a dedicated studio.
Of the 10 lockoff studios: 2 face the parking lot, 4 face the Sunset Savanna, and 4 face the pool.
Of the 8 dedicated studios: 4 face the Sunset Savanna and 4 face the pool.
The rooms are on the 5th floor of Jambo House (the AKL building). There are no Value rooms in the new Kidani Village building. There is a fantastic map here:
http://www.parkinfo2go.com/dvc-akv/floor5.php The Value rooms are located along the Giraffe and Ostrich trails at the front of the resort.
I have no idea whether checking in online will improve your chances of getting a savanna view. People are reporting that online check in doesn't allow you to make any request you want. There are just a couple of check boxes with generic choices like "close to transportation". I suggest you ask MS to add a request for a savanna view to your reservation. It's just a request and there is no guarantee that you will get it but I wouldn't assume that online check in will offer you the option to specify "savanna view".