Even with the latest version of dopus(9.0.0.6)it seems that i have the same crash with the advanced selection, on vista or XP it is the same thing, so look at theses pictures to see what i do and what happen, thanks 
You haven't specified what the string to search for. 
It looks like asking Opus to find all files containing an empty string will crash Opus. It is a meaningless search but, of course, Opus still shouldn't crash so I have filed a bug report.