Spotted in episode 108 ("Shrink Wrap"). I think it's KDE 2, judging by the icon. I don't recognise any of the software, though.
Unfortunately, this particular laptop was owned by Dr. Meridian, a manipulative psychiatrist who caused the suicides of a number of women in his care. Fortunately, Dexter deals with him good and proper...
I kinda felt that way about the entire show... Some people really loved that show and I watched it just to know what they were talking about... But for the most part I kept wondering what I was missing.
I watched all of the seasons and ultimately felt like it was a good time passer but not a particularly captivating show.
It was on a downhill for a long while before Season 8. The trope of Debra seemingly constantly being on the lookout for the least appropriate person to get in a relationship with got old pretty quick. When Debra shot her boss to cover for Dexter I stopped watching the show.