EWR Controller described an abort event when after clearing an aircraft for departure a conflict target was observed on the ASDE-X; noting the false target observed remains on the display and is simply ignored.

Narrative

I had just taken the Local Control position; landing Runway 4R; departing Runway4L. I cleared an aircraft for takeoff on 4L and as he began rolling I noticed a target on my ASDE-X on 4L at Taxiway N. I immediately canceled the takeoff clearance. The target disappeared shortly and my visual scan verified it was a false target so I re initiated the takeoff clearance. The aircraft began to roll again and then aborted. I issued taxi instructions to the aborted roll aircraft and informed the supervisor of the false target. Immediately; the supervisor asked me a series of questions to determine the nature of the target. During the time I was distracted from the position handling the false target situation; a separation issue developed on final due to compression. I wasn't briefed that false targets were appearing on the ASDE-X or that there was significant compression on final. Afterwards; I figured out that there was a wind shift on final at around 1000 feet from a crosswind to a strong headwind. This caused the lead aircraft to slow significantly more than expected when reaching a 3-4 mile final and created a 60+ knot overtake between the aircraft. The TRACON was not providing enough space to compensate for this and during the distraction period I could not recognize and/or correct the speed differential. Recommendation; I recommend that the false target problems with ASDE-X be corrected. As of today; the target is still on the display; we just ignore it now.