If you have Windows 7 or 8 installed in 64-bit mode, take advantage of running Minecraft on 64-bit Java.
Keeping your Minecraft mods organised and easy to find
Java 8 update 25 is conflicting with Minecraft Forge version 1.6.4-126.96.36.1995. If your modded 1.6.4 profiles don't open, check your Java version, you may need to downgrade.
This tutorial explains the steps to create and manage your Minecraft profiles.