Unless you can think of anything?
A small used netbook with a fast Atom / much memory might serve your purposes more than a clunky old laptop with legacy technology.
Personally the only time I was into Gateway computers was when I purchased a few touchscreens from the Olympics back a few years ago and got a deal on a few desktops purchased in bulk (new). That said I was never much impressed with the Gateway computers/laptops I saw.
Never did purchase a gateway laptop.
Base specs...googling
2.2GHz AMD Turion 64
base memory fixed (?) is 1 Gb of RAM plus 1 Gb of additional RAM
Might as well just put Ubuntu 32bit on the machine and do everything in 32bit mode.
Wondering too if it is using a SATA port or an IDE port for the drive. You can build an SSD notebook drive with an IDE port on it.
Here somewhere have an old IBM (last generation) which I did like more than the first generation Lenova laptops; but that is me.
I am not sure what your day job is; but I found that the older small netbooks with Atom based CPU's did a fine job running Ubuntu / Wintel and were tiny. Almost small enough to fit in a large back pocket.
Off on a segeway ....
I have been playing here with the new Intel Baytrail Atom CPU's. These are primarily meant for tablets but they work just fine with the new tiny Windows 8.1. You could actually install your stuff on a tiny Wintel Baytrail tablet and use a small wireless keyboard with it and maybe use a serial usb cable with it if you are looking for something small and portable for programming the Elk Panel. I am thinking now that the 4.5" tablet is around with Windows 8.1. (IE: you can purchase a mini Baytrail PC / tablet with a Wintel license for less than $100 these days).
Here just upping the memory on my favorite HP multicore laptop because originally it ran fine with the base memory on it and its just sitting and not really used in a portable sense; if that makes any sense to you.