my guess is that this position has arisen from a closed ruy lopez opening.
- material is equal and both players have no really clear weaknesses to focus on as of yet.
- white has more space because of the 2 abreast pawns in the centre.
- there are several tense spots on the board: black might take on a4 or white on b5 anytime, and black might take on d4 or white on e5 anytime. All of these options are not so good as of yet. white taking on b5 only opens up the a-file which black can use to trade off rooks and queens, and black won't take on a4 because his pawn on b5 keeps control over the c4-square. White taking on e5 would give up his nice pawn centre, black taking on d4 would give white a nice pawn centre 2 vs 1 majority.
- both player's pieces are relatively well-placed, but not really active. nothing that really can be taken advantage of.
black has some pressure on the white centre and as white isn't really threatening anything, the first thing that jumps out to me to do is to increase this pressure.
white might want to use his space advantage to initiate an attack on the kingside, for example by means of Nh2-g4.
there are no tactics in the position at the moment.
This one jumped out at me first; it grabs more space on the queenside and puts more pressure on d4, more or less prodding white to close the center with d5 or exchange on e5. The situation in the center has then cleared up and more detailed plans can be made.
This is not really to stop white from playing Ng5, but to be able to retreat the f6-knight to h7 and then maybe play it to g5.
Same thing as last move, but prevents white from playing g4 for the time being and weakens the g5-square.
Activates the 'bad' bishop. in reply to 2. g4 I can play Bf4 with a strong bishop. I would rather wait with this idea till the center is closed though.
To move the knight to f4 where it can be a pest for white, but I think white can easily stop this by playing g3.
As black I would play ..c5 which puts more pressure on white's center and ties up alot of his pieces (both knights, Bc2 and Re1 are all needed to guard the center pawns). I don't think white can do anything feasible with his other pieces so I am inclined to think that he indeed will close the center with d5, after which play will continue on the queenside and kingside.
As white I am not quite sure what I'd play at first sight. I am not so familiar with closed ruy lopez positions, so please bear with me
My first idea is g4, which is a common attacking move but usually only after the center is closed. However I assume that black's best is still ..c5 and then after closing the center with d5 I have already started an offensive on the king's wing.
My second idea is h4 to attack the fianchetto position with h5, but it will probably take a while for this advance to work (at the moment this simply loses a pawn; white doesn't have any compensation at all after Nxh5).
So, as black I would play ..c5, and with white to move I'd play g4.