Do games and internet on one computer and anything important on another not on line.
Kind of hard to do important stuff without being online; financial transactions etc. If by important, you mean stuff you want kept private then realize that hackers can piggy-back on other people's connections to the Internet. One way they do that is with parabolic dishes to catch unsecured wi-fi router connections at a remote distance miles away. If you want to hack, do it safely and remotely.