Kinda stupid question, but makes me a bit confused. If my OS (Win 7) is 64-bit type system and my CPU is 64-bit, why Program Files directory is marked (x86), x86 stands for 32-bit OS?
You should notice there are two directories for your program files. For the directory with the suffix x86 it contains the programs which are based on 32-bit addresses. Any program which is made to produce 32-bit addresses is compatible with 64-bit architecture but not vice-versa. The OS installs the programs based on 32-bit addresses in the x86 directory.