To make your job easier the Softmod Installer, it is recommended that you use the latest version of Xbox Dashboard which is available (1.00.5960.01). This is how you would check your Xbox’s Dashboard version.
1) Click on the Settings button on your Xbox Dash, press A.
MS Dashboard Settings Screen
2) Scroll down to the System Info at the bottom of the next menu, press A.
The System Info screen will give you all the information you need to know about your Xbox console including your kernel version and dashboard version.
MS Dashboard System Info Screen
3) In the system info it will display your Dashboard version. This is a screenshot of something similar to what you will want to see. The section highlighted in red shows you what your Dashboard version is. If the Xbox is not showing this version (1.00.5960.00), and you wish to keep this dashboard, you will have to use the Auto-Installer Deluxe DVD to finish off your installation.
Alternatively you can try loading a game such as Halo 2, Burnout Revenge, Splinter Cell 2 or 3 (1 is too old), and this can update your dashboard for you.