If you are honestly serious about editing I wouldn't buy a laptop. Some reasons for this:
•You can build a custom PC (or a "hackingtosh" if you prefer to use OSX) that outperforms a high end laptop for a fraction of the cost of a laptop.
•A laptop only has 1 screen(exceptions exist) which is usually to small to get any real work done on. (You'll want two big screens for a good work set-up)
•A laptop is hard to upgrade and will sooner become obsolete than a desktop.
•A laptop normally only has one CPU (most video editing is done by the processor, with the exeption of some plug-ins and 3D and ray-tracing in After Effects) and building a desktop at least gives you the option to have multiple CPU's
•A laptop is almost impossible to overclock due to the limitations on heat dissipation. (Overclocking again could be useful to increase performance and speed)
•Laptop components are generally more expensive so adding a few GB's of RAM costs a little more.
•Laptops can usually hold less RAM than PC's
•By buying a laptop you will usually also pay for useless features like optical drives and built in webcams (at least to me these are utterly obsolete)
To be honest the only upsides of a laptop are portability, small form factor and lower power consumption.
That said, it is of course possible to work on a laptop and if you are mainly looking for an excuse to get a laptop and happen to like to do some basic non intensive video altering you can do that on either of those laptops.
The N751JX looks best of the two options you supplied.
Things you want to look for in a video editing system (either PC or laptop):
•Reasonably sized (at least 250GB) SSD for your video editing software's Cache & scratch disks and installation of the OS and editing software.
•Lots of RAM (16-32GB) with a good speed (something like 1600mhz will do).
•Large screen of at least 1920x1080.
•Big secondary HDD for storage and installation of all non video editing programs.
•Fast multi core processor. Adobe usually plays nice with Intel which is sadly a little more expensive but usually more energy efficient 4 cores with hyper threading is the minimum you'd want but more is better.
A hybrid solution for maximum performance and mobility could be found in having a workstation at home which you control remotely with a cheap laptop that only functions as a "client".
For this solution to work you'd need quite a decent internet connection and the right software though otherwise the streaming lag will make certain elements of editing (specifically things like frame scrubbing) nearly impossible.
The cats are watching us...