If you refer to a word starting in upper case, like in
Substantive werden im Deutschen großgeschrieben
"großschreiben" or "groß schreiben" normally refers to the initial letter of a word only.
All uppercase is less commonly used and thus expressed by a printers' technical term as
SUBSTANTIVE kann man auch in
schreiben
Here Kapitälchen refers to a typesetting term that denotes writing a normal size capital followed by slightly undersized uppercase letters - It is also commonly used for "all CAPS", which is thus slightly off meaning.
Another technical term would be
Dieses Wort ist in VERSALIEN geschrieben
Printers and typesetters also use the term Versalsatz for all-uppercase.
(Edit: Had to change the small caps edit of SUBSTANTIVE to a picture - There was nothing wrong with it, but apparently that doesn't render properly on the mobile app)
Edit II: After you have narrowed down your question to labels in a typesetting dialog, I would recommend you use
Großschreibung
for capitalising words (although I guess typical German writers wouldn't find that function very useful) and
VERSALIEN
for all-uppercase.