In the information era, information security monitoring tools would be helpful for enterprises/organizations to monitor employees’ computer usage behaviors and improve their information security protection. The Windows-based operating systems have the largest market share in the world. Therefore, the study target is the development of a Windows-based information security monitoring tool in this study. We proposed an assessment model for developing an information security tool in this study to explore the significances of functionalities in a Windows-based information security monitoring tool and the decision-makers’ decision opinions. We adopted four steps with four study methods: the literature study method, the Delphi method, the analytic hierarchy process (AHP) method, and the analysis methods related to data-driven decision-making in the proposed model. In Step 1, we studied some literature about information security monitoring, and we discovered 26 functionalities as the decision criteria in this study. In Step 2, using the Delphi method, we confirmed the decision criterion set with potential decision-makers and organized the decision criteria hierarchy. In Step 3, we designed an AHP questionnaire to get the criterion weight vectors from the 12 decision-makers. With the AHP method, this study received the weights of the decision criteria and found that the 16 functionalities among the 26 functionalities should receive their corresponding developing priority in a Windows-based information security monitoring tool. Finally, we used the Pearson correlation coefficient and cosine distance to explore the correlations and similarities among the decision-makers’ decision opinions. This study found the relevance among the decision-makers’ decision opinions in a Windows-based information security monitoring tool developed with the Pearson correlation coefficients/the cosine distances among all pairs of decision-makers’ decision opinions.