Absolutely get her spayed. Otherwise she will continue to fight for dominance, why is she not already spayed? And why is the other dog not spayed? If they are not show dogs, it is far better for their health to get them spayed for many reasons. At 2 years old, she's got all her growth she will get in her bone structure, etc. Spaying her now will calm those raging hormones, and once that is done, you can address training issues.