OS Windows 2008 R2 Server
Processor: 64 bit

I have been given a CD of sql server 2008 when i explore th cd there is folder which has 3 sub-folders like ia64,x64,x86 and few files which including setup.exe. When i browse into these 3sub-folders i can setup100.exe in all the 3 subfolders.

I need to install sql server 2008 for x64, please suggest do i need to invoke the setup.exe in main folder or i need to invoke the setp100.exe which is present in x64 folder.

Also please suggest which is the latest SP for sql sever 2008 for x64