Ok, first, I'm kind of newbie in this area, but I highly recommend looking for a 4.6 or larger fridge. I think the 4.3 might be too small to hold the cornies and the CO2.
You do NOT need a temp controller for a fridge. You would need it for converting a FREEZER into a kegerator, but a fridge can be turned to the right temp easily.
I do not know about aging beer in a keg is any different, however, the real question about aging would pertain to the beer you were brewing. Different beer require different amounts of aging. Generally a pale ale would brew in about 2 weeks, and require 2-4 weeks conditioning. However, this really depends on you. You might like it just fine after 2 weeks of aging, so if you can manage to ferment in 7 days, and give 2 weeks aging, then you could possibly drink before Christmas.
Back to the Keg. I think what you might have understood about kegging affecting the aging of beer, is that you can CARB you beer in a day with a keg if you force carb using the high pressure shake method. As far as the beer actually aging faster, I am not aware, and frankly doesn't make a difference to me, since I will drink it early anyway.
Keep looking in the threads for info on equipment and pressure tables. You will want to get the right type of connectors for your kegs, and the right amount of hose for the beer (this is important) and know what to set the pressure at for the temp in your fridge, and for the style of beer you are serving.
If you are serving beers with two different pressure requirements, then you are going to want to get a dual regulator, so you can carb one higher than the other.
