Having reviewed the original Breiman (2001) paper as well as some other board posts, I am slightly confused with the actual procedure used by WEKAs random forest implementation.
To answer your questions
Bagging (bootstrap aggregation) is indeed used. You can view that in the code on line 529
It appears that RandomTree is used, as seen on line 530
This information is from Weka 3.7.5, I believe this is correct all the way back to version 3.6.8, but I have not checked the source code.