A few answers might help me to make some progress today ...
7a Fool in underwear during time inside home (9)
8,10 (there is a ROCK theme, assuming ROCK FORMATIONS?) Opener from Sabbath isn't safe, Christian rock (5,5)
19,25 Flash car carrying hip, grand rock group (7,6)
Very many thanks!
7a Birdbrain - 'bra' (in) 'bird (time inside; prison) in (home)'
8,10a Saint Peter - 'S(abbath) aint peter (a safe; slang)'
19,25a Rolling Stones - 'Rolls' (carrying) 'in (hip) g(rand) stone (rock)'