It means that "nice" is a compliment that is used when there is nothing better to say and you don't want to be rude. "Ganz nett" is almost certainly followed by "aber...".
If for example your publisher calls your new book "nett", he will add a reason why he will not publish it, so it may as well be "scheiße".
@EmadHariri: It all depends on how you say it. If you tell someone with a genuine smile "ich finde dich nett" and you mean it, the other person will understand it exactly as that. If someone wants to kiss you and you raise your hands and take a step back and say "ich finde dich nett, aber...", the other person will understand it as "sorry, you're not my type".
That's like in Italian. Sympathiche or something like that means nice, but in English Sympathy is not a good word because it means you feel sorry for them. I have sympathy because he has difficulty learning or I have sympathy for her because she is homeless. In English it would have a negative connotation in a way meaning that you are weaker than the normal person which in America or it can be shameful. In English sympathy is something we feel for someone that is on a lower rung than we are.
It's considered polite to capitalize "Du" and all forms of it in letters. While this is not mandatory, you can often find it in more formal contexts, like when a website adresses their guests, but doesn't use "Sie". Users on the other hand will usually write it "du" when talking to each other.
Danke schön für Ihre Erklärung. Eine deutsche Freunde von mir schreibt immer das "D" und nie das "d", und ich habe zu wissen gewollt, wenn es einen Unterschied gibt. (please correct my grammar/spelling if necessary, I don't know how to deal with zu-infinitives very well)
No, in several aspects, it's not okay.
grammar: die Frau is a feminine noun, so you have to match the ending of the pronoun: "meine Frau".
vocabulary: schon (=already) is a completely different word than schön (=pretty). What you wrote means something like "I will find you". If you can't type Umlauts, write 'ue', 'oe', 'ae' instead to keep the meaning of the word.
idiomatic: "meine Frau" is usually understood as "my wife". Even if that's what (and who) you meant, you don't really address your spouse with "meine Frau". You would say "mein Schatz" or something similar.
They are two different vocables referring to the same thing but with different grammatical context. It's like saying "are I and me the same?" They refer to the same person, but used in different grammatical positions. "Du" is nominative, usually used as subject of a sentence. "Dich" is accussative, used as the object of a sentence:
"Ich sehe dich" = I see you
"Du siehst mich" = You see me