As I've mentioned earlier to Ryan, ProcessWire runs fine on Windows 7/2008 Server setup with IIS 7.5 WebServer with IIS Mod-Rewrite from Micronovae that can read .htaccess file. The problem is that this IIS filter is free for development use on localhost without limitations but it's not free for production use on live server (it costs $150 per server license).
I've found another solution that works flawlessly and it's absolutely free.
- Download URL Rewrite Module 2.0 for IIS from http://www.iis.net/download/urlrewrite and install it
- Define new web site under "sites" in IIS Manager and point it to directory where you've unzipped ProcessWire files
- Download web.config (translated from original .htaccess) file from this post, unzip it and put it in ProcessWire root directory
- Delete .htaccess file (because you don't need it any more).
I hope that this will help someone if the need arises for ProcessWire use on this kind of install.