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I am looking for a good, fool proof grape wine recipe. One that does not rely on just the grapes.

Before any real techo replies, the whole thing about grapes is that people have been making wine from just grapes for thousands of years and given normally cleanliness it is 'foolproof'. The only thing is if the grapes are not very ripe then the wine may only be 9% alcohol rather than the more usual 11 or 12% (although some German wines are often sold at 9%). You can boost the alcohol by adding sugar but the amount to be added can only be calculated after measuring the grape juice with a ...... (sorry forgotten name, a simple little tool), otherwise it is just a guess.
You can add yeast but it is not necessary, there is yeast on the grapes. No ordinary frenchman would dream of adding yeast.
You don't say whether you want to make white, red or rose wine. Assuming red or white (and not white from red grapes) the process is basically the same. Crush the grapes (just to break their skins) and put in a container. Cover container with a cover to keep out fruit flies (eg. polythene with elasticated tie). When wine ferments, the skins will be forced to the top, these need pushing back down twice a day. After fermentation has finished in about 2 - 3 weeks, drain off the liguid and store. The remaining skins, etc can be pressed (if you have press) to extract the last of the juice which is added to the liquid you have already drawn off.
This juice from the press is inferior quality to that just drawn off. However with red wines in particular it gives 'body' because of the tannins in it. For white wine it is less useful taste wise.
The wine then needs to be stored in a cool stable temperature (and this is probably the most important thing in producing a 'foolproof' wine) for about 6 months before drinking.

I'll second what graham says. Grapes are traditionally used for wine because they have the perfect mix of ingredients for wine - the bloom is the yeast, they contain the right amount of pectin, tannin, sugar and water. Whenever you add something artificial, it adds risk to the process.

I've made grape wine for 4 years now without ever having a bad batch, using the technique outlined above.

I didn't have time to use my grapes when I first harvested them, so I froze them. As there wasn't enough room in the freezer for that many whole grapes, I whizzed them in the blender first. Saved loads of space, but do you think they will still be OK to use as-is? I can't think why they wouldn't be, it's just my first ever wine-sized batch of grapes so it would be a shame to mess up.