フリーで映画やドラマが見れるサイトがあるのですが、
観たい番組をクリックするとき、下記のメッセージが出てきて、観れません。
「このサイトには次のＡｃｔｉｖｅＸコントロールが必要な可能性があります。”DivX Inc"からのDivX（Ｒ）Web Player”をインストールをするにはここをクリックしてください。」
これはインストールしても大丈夫なのでしょうか？

パソコンに詳しい方ご教示願います。

Active X control is something that you should be very careful about when asked to download it. Make sure the site that is asking you to download it is legitimate (ie: it is the website that it says it is). In order to do this, check its security certificate. Basically it’s like a small "software" that ’sits" on your computer to execute a specific command. To learn more, do a google search and you will get more info. The reason why I say that you should be very careful is because if it’s not from a legitimate or trustworthy site, then it could have Trojans, worms, and other nasties hidden inside. For example, when updating your Windows OS by going to the Windows update site, Microsoft asks you to install its Active X Control. There are some security programs such as McAfee which allows you to remove any Active X control that you install. For safety precautions, I always remove any Active X.