The best way to store all results of a test into one file is to create a DOC file.
If you have Microsoft Office installed on the client machine, click on Report (Word) after a test is finished:

Select what data you want included in the report. As soon as you click OK, Microsoft Word is started using OLE and the report is built. A few seconds later you can edit, print and save the report using all the normal functions of Microsoft Word.

Webserver Stress Tool is a powerful HTTP-client/server test application designed to pinpoint critical performance issues in your web site or web server that may prevent optimal experience for your site's visitors.
Welcome
Introduction: Testing Basics
Performance, Load or Stress Testing?
Calculation of Load and Load Pattern
Webserver Stress Tool Features
How much load can Webserver Stress Tool generate?
Installation
Configuring Webserver Stress Tool
Selecting the Test Type and the Number of Users
Selecting the URLs or Editing the URL Script
Using Custom URL Scripts for Advanced URL Sequences
Performance Tips&Tricks
Running the Test
Reviewing Logfile Results
Analyzing Graphical Results
Graph Click Times & Errors (per URL)
Graph Click Times, Hits/s and Clicks/s
Graph Server and User Bandwidth
Creating Reports
Additional Features
Appendix
Software License and Contact Information