Surge Protectors do two things; it will protect the connections inside your home theatre system and provide you with a central location for all power connections. Sure, you can monitor the weather channel and unplug your entire unit before every thunderstorm, but not only is that unrealistic, it won't help stop voltage spikes. Not to mention the many DVD players, VCR or cable boxes have to be reprogrammed when unplugged, which becomes quite the nuisance. Purchasing a surge protector eliminates this headache, provides a place for all power connections and simplifies the ability to track multiple cables. If you already own one and it doesn't have labels, make your own, it is worth the effort.
Surge protectors come in various sizes and plug inputs, being aware of how many you need and how many units you intend to add in the future is important before purchasing. An often overlooked aspect of these tools is that ALL LINES INTO YOUR HOME THEATRE NEED TO BE PROTECTED. Not just the power cables. In other words, the cable connection, any outdoor antenna or phone line is just as important as the power cable. There is a surge protector out there that addresses all these needs, do a little research and buy the appropriate model.
When looking into a surge protector be aware of the shut off limits. Problems only occur when the voltage fluctuates too for above or below the acceptable limits. This happens very quickly and you want to be able to respond in less than a nanosecond. The level of protection increases based on quality of surge protector. Look for one with visual indicators that will quickly tell important information, as well as audible indicators that will sound when a power surge has taken place. Also look into surge protectors that address the filtering of electromagnetic and radio frequency versus those that do not. These will produce cleaner power, which provide a greater protection level.
Finally, make sure you are presented a warrantee that guarantees coverage of the complete value of your home theatre system, not just the surge protector. If this is not available, it is not worth purchasing the equipment in the first place.
The point with all of this is to be a step ahead of any potential problems regarding power surges or voltage fluctuations. Investing in expensive equipment and not a surge protector is foolish and is asking for trouble. Be proactive, be preventive. Make your home a SmartHome.