I applaud you for making the changes in your life that sets you truly free from satan's bondage. The internet is tempting place that ruins marriages every day. It is better to get rid of you computer completely and go to the library to use one that to have something in your home that could destroy your family if the temptation becomes to great.
God will always encourage you to be completely honest. Any secret you keep from your spouse has the potential to come back on you. If she really loves you she will appreciate your honesty and she will know she can trust you to tell her the truth even when it's hard. However should she somehow find out on her own, it will damage the trust she is placing back in you. You can never go wrong being completely honest, a woman needs above all else to have the security of faith in her husband. In always being 100% transparent satan then has nothing to hold over on you or to make you make you feel guilty with later.
Best of luck to you and your family