Actually, you should not store wine in the fridge. If the wines have corks, the lack of humidity will dry them out, making the undrinkable rather rapidly, and as corks are porous, flavours and odours may permeate and ruin the flavour.
If they aren't with cork, you run into additional problems stemming from the vibrations of the fridge, the off & on lights 10+ times a day, and several other issues.
Put the Chard in the fridge a few hours before you want to drink it. If we are talking red zin (which I will assume since you didn't specify "white"), then maybe 30 minutes before serving.
Until then, store horizontally (on their sides) in a cool, dark closet.
As far as saving them - this will depend on how far away the event is and the quality of the wine. If the wines were under around $30, chances are good that they should be consumed within a year. If they were above, chances are they should be held at least a year. Something like 80% of the wine produced (not sure of the actual number) is ready to drink, so make sure that you don't hold it too long.
I hope this helps.