1. A computer system comprising: a processor, a computer readable memory, and a computer readable storage medium; first program instructions to provide a computer tool with a defined rating system for a business software application, wherein the defined rating system establishes a rating of how effective the business software application is in meeting pre-determined requirements for each one of a set of business technology factors, wherein the set of business technology factors comprises: a business function factor, wherein the business function factor is defined as a measure of how successful the business software application is in meeting user-defined needs for operations within an enterprise, a business fit factor, wherein the business fit factor is defined as a measure of how successful the business software application is in meeting stated goals of the enterprise, a business criticality factor, wherein the business criticality factor is defined as a measure of how critical the operations within the enterprise are to meeting the stated goals of the enterprise, and a software enterprise factor, wherein the software enterprise factor is defined as a measure of how compatible the business software application is with existing servers in the enterprise; second program instructions to receive an input, into said computer tool, of rating values for the business software application, wherein the rating values describe how effective the business software application is in meeting the pre-determined requirements of each one of the set of business technology factors; third program instructions to conduct an architectural fit analysis to evaluate an architectural fit of said business software application based on inputted said rating values, wherein the architectural fit analysis is performed by the processor utilizing inputted said rating values for the business software application and other software applications for comparing the business software application with the other software applications, wherein said comparing determines which software application provides a best architectural fit based on inputted rating values for the business software application and the other software applications; fourth program instructions to generate an analysis report based on the architectural fit analysis, wherein the analysis report describes which software application provides the best architectural fit for meeting the pre-determined requirements for all of the set of business technology factors; and fifth program instructions to install a software application that provides the best architectural fit for meeting the pre-determined requirements for all of the set of business technology factors; and wherein the first, second, third, fourth, and fifth program instructions are stored on the computer readable storage medium for execution by the processor via the computer readable memory.