04-18-2011, 12:03 AM
You can have both version of Java installed. The start scripts should automatically select the right version, ie the x86 will find the 32bit installation and use it, the amd64 will find the 64bit installation. As for Minecraft, how is the launcher ? Is it just a simple JAR file to launch ? If that's the case, you can right click the file in Windows explorer and use the "Open with" submenu to chose the right JVM.
Have fun !
Have fun !