How do phospholipids and proteins assemble to form a biological membrane?

lipids are excluded from the water b/c of anti-entropic effects.  thhe bilayer forms because phosphoipids contain a polar head group that likes to interact with water.

proteins are put there at the time of translation and stabilized within the membrane by hydrophobic interactions with the lipids

Well the membrane pretty much concsists of Phospholipid heads which are Hydrophilic (Attracted to water) and Phospholipid tails (which are composed of lipids) are Hydrophobic (Repelled from water).  Many of the proteins that become "lodged" or stuck inside the membrane are  Amphiphilic which means they have regions that are Hydrophilic and regions that are Hydrophobic.  This combination allows for proteins to become part of the membrane (also called integral proteins) and proteins that  lay on top of the membrane (which are called peripheral proteins).  Depending on the protein and its location they have different functions, such as the transport of ions through their concentration gradient.  

Hope this helps!

Phospholipids contain a polar and an unpolar part. The unpolar part can bind weakly to the unpolar parts of other phospholipid molecules, but not to water, whereas the polar part can bind water, but not unpolar molecules; thus the unpolar parts bind to each other, form a layer, and on the surface of the layer that will become the membrane are the polar parts because there is water in the cell and outside the cell. Proteins must have an unpolar part, a so-called transmembrane domain, to be anchored in the membrane.