What resolution should I choose?

I want to create a game with pixel-art graphics. The game will be consist of the one room and I want to paint this room, but I don’t know, what resolution should I choose for it. On my computer display’s resolution is 1366x768. But would it displays correct on the other computers with another resolution?

1.) Create a Guitexture set Scale at 1, 1, 1
2.) Drop this script into that Guitexture and set value as 1, 1;
3.) Set 0 at Pixel Inset under Guitexture Component.

using UnityEngine;
using System.Collections;

public class GUIAspectRatioScale : MonoBehaviour 
	public Vector2 scaleOnRatio1 = new Vector2(0.1f, 0.1f);
	private Transform myTrans;
	private float widthHeightRatio;
	void Start () 
		myTrans = transform;
	void SetScale()
		widthHeightRatio = (float)Screen.width/Screen.height;
		myTrans.localScale = new Vector3 (scaleOnRatio1.x, widthHeightRatio * scaleOnRatio1.y, 1);

This script will help to fix your background resolution problem, there are more matrix solution in Here or you can use this code snippet under you OnGUI()

void OnGUI()
		Vector3 scale;
		float ResolutionX 	= 1920;
		float ResolutionY 	= 1080;
		scale.x 			= (float)Screen.width/ResolutionX;
		scale.y 			= (float)Screen.height/ResolutionY;
		scale.z 			= 1;
		Matrix4x4 svMat 	= GUI.matrix;
		GUI.matrix 			= Matrix4x4.TRS(new Vector3(0,0,0),Quaternion.identity,scale);

This will scale your button or images.