the one I linked to is refurbished.. but morgan computers is a reputable company.
Karens is new, but doesn't have windows installed, it has linux (a cut down version at that!) and no CD drive at all, so installing windows would be tricky or require a USB CD drive.
Chris's one is a respectable computer for the price... but is a single core p4 (old) CPU and only 1GB of ram and a 40GB hard drive, which will quickly become not big enough these days.
None of them (including my link) are really suitable for gaming, but they will give much better performance on basic stuff like minecraft than a netbook.