Let's clarify some stuff:
You just need to see pixels size of width and height, resolution is a field related to printing or monitor resolution but it's not referred to the size, it can have any value in your case that makes no difference if you keep your desired pixel size.
Resize before you edit and use bicubic method. If you scale up a bmp, pixelated image is normal, less if you scale down. Not pixelated if you have vector image.
Still problems?