6. Are those expensive Riedel glasses worth the money?

Yes.

(and Reidel isn't the only brand worth considering - Spiegleau is
another). They are not all that expensive - one can get very nice
glasses for about ten dollars (US) a stem, although they do go up from
there for those with the money. When you consider the total value of
the wine that will be poured into these glasses over the course of a
year or so, the price of the glass is very small indeed.

Scent (the "nose" of a wine) is easily as important as the other taste
sensations. Red wines tend to have a fuller nose, and the larger globe
style stemware is very effective in capturing the aromatic vapors the
wine gives off so they can be enjoyed. One should fill the glass only
part way, typically to the widest part of the globe, leaving a lot of
space for the nose to gather (and a lot of room to swirl the glass,
encouraging the release of these volitile elements). Although white
wines will do well enough in a "red wine" glass, a narrower vessel helps
show them off better. The same ideas apply however, fill the glass only
partway, to leave room for the nose.

The thinness of the rim of these glasses is more pleasant to many than a
thicker rimmed glass, and allows the sensations of the wine itself to
dominate. Thin glass also does not affect the temperature of the wine
as much as a thicker glass, although there is some controversy about how
much this matters over the course of a meal, since the wine will be
changing temperature anyway.

Champaigne and other sparkling wines should be served in a flute style
glass. This keeps the effervescence from disspiating too soon. Coupe
style glasses (the old classic with the shallow, wide bowl) are probably
the worst thing to do to champaigne, because the bubbles will dissipate
too quickly. Save the coupe glasses however; they make beautiful
dessert vessels.

Beyond this, it is not necessary to get a different kind of glass for
each style of wine; one can easily go overboard here. A simple globe
style red wine glass is sufficient, though you may want another glass
with a narrower bowl for white wines. Anybody who can appreciate the
finer differences between all the other kinds of glasses probably
doesn't need the faq in the first place!

Holding the wine glass by the stem keeps your hand from warming the wine
up as you drink it, which is why most wine glasses are stemware.
However, some places serve wine in non-stemware, notably the Healdsburg
Bar & Grill in California (http://www.hbg4fun.com/), which uses them in
their outdoor dining area, because non-stemware has a lower center of
gravity and is more stable on tables that might rock or be bumped.

====

4. What is the best way to preserve an opened bottle of wine? How long
will it last?

I'd edit the end of paragraph 3 thus:

Probably the best method is to rebottle the wine in a smaller bottle
[...]. Be sure to label the bottle! If you have smaller bottles that
have screwcap closures, they are even better for storing excess wine.
Although it seems that one could put the bottle back in the cellar for
another year, this may be optomistic. A winery bottling plant is ultra
clean. They sanitze the bottle, and purge the oxygen from the bottle
both before and after filling the bottle with wine. They also monitor
the oxygen level continuously, and stop the plant if excess oxygen is
detected. If you rebottle at home you are not likely to have these same
conditions, so putting it back in the cellar to age some more is
probably not reccomended.

Jose
--
"Never trust anything that can think for itself, if you can't see where
it keeps its brain." (chapter 10 of book 3 - Harry Potter).
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