I won't mention the two most popular options; BlueStacks and Andyroid since several people already suggest them, instead, I will suggest some others.
Here's a few to try out:
-
AMIDuOS; it only requires 2GB RAM, however, it is paid. You have a trial version as well I think 25 or 30 days then you have to purchase the software to keep using it. If interested, use the trial option to see how well the emulator would work for you then decide. Also, it doesn't support Windows XP but I don't know if you're still using it or have upgraded (
http://www.amiduos.com/)
-
Jar of Beans; a great software, supports Windows XP and other versions as well. It is completely free and really easy to set up. I have used it before and have great experience!
-
KoPlayer; one of the best free software available. It is really amazing, runs smooth and has features that some other free emulators don't such as the video recording of the screen (
http://www.koplayer.com/)
-
YouWave; another software that runs perfectly on Windows XP. But it is paid. Not too expensive though (
https://youwave.com/).
Hope any of these fit your needs