Once you have installed Halo 2 simply install Games for windows live, or if you have another games for windows live game you have already gotten to work you can simply reinstall the game you got to work earlier.
doesnt have a high enough graphics card
Only Windows 64-bit operating systems can run 64-bit applications
Yes. I have viva pinata and windows 7 64 bit, and it runs perfectly!
To use 64-bit specific applications, you must purchase both a 64-bit processor and a 64-bit version of Windows. 64-bit applications will not run on 32-bit versions of Windows, even if a 64-bit capable processor is installed. You also cannot install a 64-bit version of Windows on a 32-bit only processor.
Yes. It can run either the 32-bit or the 64-bit version of Windows 8. I'd recommend the 64-bit version.
Yes.
No you can't because 64-bit won't run on an x86 (32-bit) PC. You have to have the x86 version.
Supposedly there is no scmpoo for windows 7 64-bit. In order to run it you have to download and run Virtual PC and use SCMPOO in the virtualized Windows XP.
No, unless you are running programs optimized for 64 bit windows, and the vast majority (99.some percent) are not. The main advantage of 64 bit windows is support for crazy large amounts of memory (>4GB)
Yes.
It is impossible to run 64 bit applications on a 32 bit based system. You can upgrade to a 64 bit version of Windows XP, Windows Vista and Windows 7... unless you use a Virtual Machine to run a 64 bit OS. Note that this could be very bad to use if your computer is physically not capable of running a 64 bit OS.
No special action is needed. 32-bit applications are run transparently.