How do wine glasses affect the taste of wine?

Tall and sweet or wide and dry?

The wine glasses don't actually alter the taste of the wine itself, as you can probably imagine, but they do alter our perceptions of what we're drinking.  Most important is that you base your wine glass purchase on personal preference.  No two people will perceive the same variations in wine based on eccentricities in their wine glasses, which include not only shape and size but visual appeal and aroma.  Your visual perception is based on how your wine reflects light, and how the wine changes shape and form (forming legs) when you swish it around in your glass.  Your wine glass will also determine your perception of its aroma prior to taking a sip.

Which wines go with which glass?

Traditionally larger, broader glasses are used for heavier wines, such as reds, and narrow glasses are used for lighter wines, such as whites.  The broader the glass the more the wine is allowed to breathe, while narrow glasses tend to hold the temperature of the wine longer - a desirable effect when serving a chilled white or desert wine.  An example of the visual appeal of a beverage in a glass comes to mind when we think of the tall, slender glass that holds a bubbly Champagne.  The California Wine Institute developed an all-purpose 8 ounce wine glass that is 5.5 inches tall with a 1.75 inch stem.