Problem in debrust method

hi all,
after coregistration of two SLC image when i try to debrust the image after end of the processing when i open it, its open the half portion of the image. how can i solve the problem. I am using i5 computer with 4gb ram.
and my another question is what is the right procedure for generate a good InSAR DEM. i follow the steps as shown in the manual but the interferogram is not good.interferometry_flt.dim (2.3 MB)

Sounds like an out-of-memory issue…