Hi!
Looks like little bitty Phillips screws to me, very common on laptops and other electronics.
Any set of "jeweler's screwdrivers" will do the job for you. Go for cheap. Who needs quality for what you're dealing with.
This is what they look like:
http://www.ebay.com/sch/i.html?LH_BIN=1&_sacat=0&_from=R40&_nkw=jewelers%20screwdrivers&_sop=15
Incidentally, these SAME sets go for $1.00 in the dollar stores around here. The cheapest on Ebay are around $3.29, or so, shipping included.
You can pay five times as much and get twice as many drivers of equivalent quality (or lack thereof) at Radio Shack:
http://www.radioshack.com/product/index.jsp?productId=3932541
However, I haven't found bargains at Radio Shack for the last fifty years. You pay for the convenience of having stuff available, and for the insolence of some arrogant adolescent sneering at (what he thinks is) your technical ignorance. In this case, I would go to the closest dollar store and get the same convenience for very small change without insults.
By the way, I have found you can increase the torque of these small drivers by gripping them in a pair of pliers. That can help if you encounter overly tightened or glued solid screws.
Good luck to you.