What's a good mining software to use on Windows?

If you do not have a dedicated rig for mining I would advise against mining. It is very hard on your components and will cause your electricity bill to increase substantially. That being said, and assuming you do not care about either of these factors, Minergate may be a good optioni.

Again, I do not recommend mining with your personal computer as it is very hard on your components (your GPU particularly) and will drastically shorten its lifespan.