Unfortunately, mother's names don't appear on marriage certificates!
But the 1911 census entry certainly looks like your Hilda. However, I cannot find a SMALLWOOD/HIGNETT marriage. Hilda's birth certificate (obtainable direct from the GRO via www.gro.gov.uk
for £9.25) would be your next step. Here is the reference:
Births Sep 1909
HIGNETT Hilda W. Derby 8b 498
But it would still be good to try and decipher that marriage certificate!