Neither one of them is a great deal. EWR does seem to have more that it's fair share of delays. It also has very limitied parking. I have never parked any closer than the furthest lot. The monorail system is ok when it works, but I sat in between stations several weeks ago during an ice storm for almost 35 minutes....at 1:A.M in the morning!!!
If your flying overseas, you don't have much choice. If your flying within the US, you may want to consider LGA, or even Westchester County (HPN). Depends on where you live. I fly out of Stewart Airport (SWF) in Newburgh, NY quite often. It doesn't have a whole lot of flights, but you can be in and/or out of there in very little time. It's the best of both worlds - small convenient terminal...BIG 11,000 foot runway (13,000 with thresholds). It also has an Air National Guard wing of C-5 Galaxy cargo aricraft, which can make for some good plane spotting if you have extra time.