Near solar maximum (which happens every 11 years approximately), there are many more solar flares and coronal mass ejections than near solar minimum. Flares and mass ejections are no danger for humans or other life on Earth. They could endanger astronauts in deep space or on the Moon, and this is something that NASA must learn to deal with, but it is not a problem for you or me.
Large outbursts can interrupt radio transmission, cause bright displays of the aurora (Northern and Southern Lights), and damage the electronics of some satellites in space. Today many satellites are designed to deal with this possibility, for example by switching off some of their more delicate circuits and going into a “safe” mode for a few hours. In extreme cases solar activity can also disrupt electrical transmissions on the ground, possibly leading to electrical blackouts, but this is rare.
The last solar maximum occurred in 2001, so the next one was predicted for around 2012, 11 years later. However, the most recent solar minimum was unusual, with a period of a couple of years with almost no sunspots or other indications of solar activity, so scientists now guess that the next maximum will be delayed, perhaps to 2013. However, the details of the solar cycle remain basically unpredictable.
You are correct that the Earth’s magnetic field protects us by creating a large region in space, called the Earth’s magnetosphere, within which most of the material ejected from the Sun is captured or deflected, but there is no reason to expect a reversal of magnetic polarity any time soon. These magnetic reversals happen only once in 400,000 years on average.
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