The 1GB SD card is all you need, so don't worry about this (see e.g. http://rickardnobel.se/esxi-5-0-partitions/).
Regarding the RAID, it is either configured with a hot spare or in RAID10. I'm not sure whether DELL provides tools to check this in ESXi, but you can definitely check the configuration (and reconfigure it if required) in the RAID controller's BIOS at boot time.
André