Wanting your thoughts..

1. If you have any interest in doing so, build your own. You'll get better parts for the money (and possibly spend less), and you'll know the ins and outs of it to be able to fix it. All you need is average manual dexterity and eyesight, a Phillips screwdriver, and perhaps a pair of needlenose pliers (to more easily place front-panel connectors and/or fan cables).
2. If you really want to buy something, of those two the Tigerdirect PC is unfit for purpose for being too weak, and the Newegg one won't last due to its cheap MSI mobo and a PSU-shaped object, and its graphics card is really the minimum you'd want.

Take a look at this quarter's $750SBM build. If you need to, cut the graphics card down to a GTX760. You'll blow the side panels off either of these prebuilts.