Well before windows starts the process it calls NtCreateProcess() or NtCreateSection() and so on... i would like to deny some processes before they are able to start theire code.
It must be possible to tell windows

Windows: I want to start this process.
Me : Ok ... but please wait i check name and checksum
Windows: failed to start process
Me: check is ok now i start process xyz
 ||
Me : check failed i won't start process
[download]

here my inspiration http://www.codeproject.com/KB/system/soviet_protector.aspx
thanks for your reply