AgTip, like Yoda said, the THANKS button is only visible if you have logged in to your member account, then go to the threads with useful posts and you click the "Thanks" button on each post that you consider helpful, you can do this even if you did not start the thread.
Now, about your question, If you install 32bit programs on a 32-bit OS or 64bit programs on a 64-bit OS "well behaved" Programs are supposed to install under the %ProgramFiles% directory, which by default is "C:\Program Files". A 32-bit program under a 64-bit OS should install under %ProgramFiles(x86)% which by default is "C:\Program Files (x86)". These environment variables are set on boot up based on registry settings. You can change them but IF you do it is best to do it right after a fresh OS install, before any programs are installed. If you want to change it on an install by install basis, some install programs allow it on the first screen, for many you may need to choose "Custom" install.
If you are interested in the other environment variables check here...
http://en.wikipedia.org/wiki/Environ...rosoft_Windows
If you want to know how to change default system directories let me know and I'll look it up.