Opinion - Optimum life of white wine
for now, letting the higher-echelon Burgundies in the basement rest 7-8 years and longer with no worries ; people have enjoyed those wines a long time and written plenty about them. the whites with moderate age that have pleased me the most (at least until those Meursaults et.al get opened) have been chenin blancs from the Loire, and recently, a melon de bourgogne, Domaine de l'Ecu, Muscadet Sevre et Maine sur lie (Guy Bossard), 2004. the Bossard wine was one of the most satisfying whites in my experience, complex, balanced, still vibrant. Some Rhone whites are also cellared successfully, and of the Italian whites, you might do better with some of the northern wines like vermentino or pinot bianco. my basement does have a bottle or two of fiano di avellino and greco di tufo, so they'll be my experiment with moderate aging for the Campania wines.
That depends on what you like.
I enjoy well-stored white Burgs, with some age on them. Many others do not. Same for some domestic (US) whites. Many change, and in a good way, but many do not. It depends on the wine.
Same goes for great Rieslings. Some "improve" with a few years, but no all.
What do you like?
I would have to assume you know that aged white Burgs are among the finest wines in the world. It is not a question of "if" they can be aged. It would be like asking if "Bordeaux can be aged"????? ..........are you looking for rec's?
I don't have experience with Campania.
Rieslings are very age worthy but the masses prefer them younger. I appreciate them aged and they are quite different than when young. I did a post on aged Reisling and milk chocolate here once (I think).They are fairly inexpensive to buy and hold. You can often find aged German Reislings that are very affordable and reliably drinkable (they tend to be "sturdier" than other whites for aging). But, I would suggest you try an aged Reisling first to see if you like them aged...some love them...some think they taste like a mix of diesel and ass.
It's very difficult to generalize about White Burgundy and Riesling. Somewhat easier for Campania.
White Bugundy will consist of regional wines, multiple village wines, single village wines, premier cru wines, and grand cru wines. This last group tends to be the most "ageworthy," and in goog vintages can easily go 20 years.
Riesling also as regional wines, village wines, and vineyard wines. German Riesling is also labeled according to when the grapes were harvested (meaning how much sugar was in the grapes when they were picked). Generally later harvested wines are longer lived. But I've had 30-year old riesling spatlese from excellent vintages that have been holding up incredibly well. Then there are rieslings from Austira, Alsace, Australia, Washington, California. So, again, hard to generalize.
The whites of Campania (Fiano, Greco di Tufo, Falanghina, etc) generally show much better when younger, and typically don't develop the complexity of a mature Burgundy or Riesling.
Of course with all of these, there's also the variables of vintage quality and producer.
If you have specific wines in your conditioned cellar that your are particularly interested about, it might be helpful to list those instead of bank on a limited generalization.
It depends on the varietal, what you like in your wines, the vintage etc. Cellartracker is a great resource for looking up a particular bottle and see notes on it. I can try to speak generally to White Burgandies and Rieslings.
The great white wines of Burgandy traditionally age quite well. They have lots of acid to age against. They also can have a lot of oak in the beginning that I don't particularly like in my wines. If one likes primary fruit flavors, with the oaks and acids tempered and well integrated, they will tend to be at their best about 5-10 years after the vintage. Now, some may like the secondary characteristics that come out as the wine develops and will hold onto these wines much longer. There is always the risk (and it's become more of a risk lately) that the wine will oxidize and deaden if one keeps white Burgandies around too long.
I like drinking Rieslings right after they are released through about 4 years after the vintage. I really like the primary fruit/floral characteristics at the beginning. Those who like the aged characteristics of old Rieslings (petrol and other characteristics) will hold onto their wines for 25+ years. There's tons of acids in rieslings with many vivid flavors and so they age quite quite well.