To clear up the C:\Program Files (x86)\ issue:
The majority of computers out there either run 32-bit (can use up to 3GB of RAM efficiently) or 64-bit (can use up to 8GB of RAM efficiently) operating systems.
32bit applications can run on 64bit machines, but 64bit applications cannot run on 32bit machines.
In 64bit installations of Windows, 32bit applications are stored in the C:\Program Files (x86)\ folder instead of C:\Program Files\, which is for native 64bit applications.
x86 = 32bit
x64 = 64bit
I'm pretty sure that there's no 64bit version of Blockland, so it will be installed in C:\Program Files (x86)\. 64bit vs 32bit is a different version of the operating system. I think certain computers can only handle 32bit, 64bit, 16bit or whatever.
Somebody correct me if I'm wrong there (or anywhere).
Internet Explorer
Why would you use Internet Explorer in the first place?