1) You can use the SSD under either raid mode or ahci mode, because when you enable the raid that will enable AHCI too.
2) When you install the new OS into the SSD, you are better only connect the SSD but not other storage drive because during the installation if you have other HDD then some of files/folds will be installed into those HDD. Later on you will get problem.
3) The Samsung Magician Software may not work under the raid mode, I have the ocz SSD in raid mode and the toolbox does not work under the raid mode.
4) If you want to dual boot the SSD with win7 ult and the HDD with win7 enterprise, then you may need use the " easyBCD' to build the boot loader. http://neosmart.net/EasyBCD/
5) So you connect the SSD, install the win7 ult, shutdown the laptop, connect the hdd, reboot the laptop, build the boot loader, then you may can dual boot.