Restoring laptop to factory image using recovery partition (no backup dvd only recovery partition)

Hi,

I have an Inspiron 15R SE with (Bundled with Windows 8). I installed Windows Server on the main drive. Now I need to restore it back to the factory state. What are the recommended ways to do it?

I dont have any dell software on my machine right now. I didn't touch the recovery partition so it should be intact. I didn't create any factory image backup so all I have is the recovery partition.

Should I install dell recovery software and start from there or do I need to somehow boot into recovery partition and do the recovery? 

I'm not doing any recovery till I hear from you guys so please try to help me :)

Thanks in Advance