Yep those are the screw that hold the fan and heatsink firmly in contact with the CPU, the screws can be loosened completely, they will not fall out, then slightly with very little pressure rotate the assembly to break it free from the thermal compound. Once its removed you will notice what look like a latch that clamps the cpu into the socket. Undo the latch and the CPU can be removed. Be very carefull when you have the cpu out, you will notice very small "pins" in the socket. Do Not let anything get in the socket of on the bottom of the cpu. Good luck, it's not difficult and after you do it you'll think, that wasn't so bad.
tyler_55 :
t53186 :
The screws hold the heatsink in place on top of the cpu, it will heed to be removed first. After removing the screws, CAUTION use very light twisting motion to "break" the bond between the heat sink and top of cpu. Thermal compound (grease) or a thermal pad is used between both to conduct heat to the heatsink. Once the heatsink is removed you will need to release whatever locking mechanism is used to secure the socket cpu in the cpu socket.
More detail about what type motherboard socket or cpu would be helpful to give you more specific details or pics of the process.
Okay so here is what the screws look like I hope this is clear enough
http://imgur.com/a/fN2Z0
The mobo is a Lga 1151 and a H110 Express.