no need to excuse for your English. It´s perfectly readable.
Unfortunately you are not very specific about your scenario.
E.g. what kind of OS will by installed. I haven´t tinkered
around with the VBox API but there are multiple approaches
for this scenario. If you want to install certain programs
during a Windows Installations within the VM, you could integrate
them into your Win boot ISO with tools like NLite. You could also
use tools similar to psexec to lauch setup programs within your
VM in silent mode.
See here for details:http://technet.microsoft.com/en-us/sysi ... 97553.aspx
Automated execution of AutoIt script after first startup could be another option.
For Linux guests on the other hands you could use simple shell scripts to connect to your guest via SSH and execute the tools of your choice.
Hope this helps somewhat,