You only get two DDR2 memory slots but that's hardly likely to hold you back or upset your plans for an upgrade and neither should the lack of RAID on the ICH7 Southbridge cause any concerns. There is some merit in using the old ICH7 as it has native support for an IDE connector, unlike Intel's more recent chipsets which have inexplicably dropped this part. The IDE, floppy and main power connectors are outboard of the memory and are easy to reach but the four-pin ATX 12V connector is in an awkward location behind the I/O panel and between some tall capacitors - all rather too close to the processor socket as well.
There's a spare system fan connector but we doubt that you'll need it as the Gigabyte is a cool customer. It helps that the Core 2 Duo needs very little cooling and when we ran the GA-G31MX-S2 with a Core 2 Duo E6750 at 2.67GHz with 2GB of OCZ Reaper memory and a Sapphire Radeon X1950GT graphics card, the passive heatsinks on the board remained cool to the touch.
The Northbridge cooler ran at 35 degrees during benchmarking and the Southbridge cooler was only a little warmer at 43 degrees. When we overclocked the CPU to 3.20GHz the temperatures rose slightly to 37 degrees and 49 degrees respectively but we don't recommend overclocking this board as it causes problems. The processor we used has happily run at 3.52GHz on a 440MHz FSB on other motherboards but here it topped out at 3.20GHz and start-up was an unpleasant process where the Gigabyte declared that ‘No Boot Drive was present' shortly before Windows did, indeed, start.
At 3.36GHz we could run PCMark05 but 3DMark06 caused the PC to restart. Mind you, according to Intel our E6750 shouldn't have run in the first place as the G31 isn't supposed to support the new 333MHz/1333MHz FSB. Happily Gigabyte disagrees.
The GA-G31MX-S2 is absurdly cheap and it'll be absolutely fine if you're building a basic Core 2 Duo PC for your mum. However, gamers, home entertainment enthusiasts and overclockers should give it a wide berth.