Dear Sppeeedy,
viDrop is a GUI-frontend for the program MEncoder. This program could be found on
www.mplayerhq.hu - including a description of many parameters. To get Sound & Picture in Sync you should experimental with the parameter -Delay=(milliseconds from 0 untill 999) as "Extra Parameters for MEncoder" in viDrop. viDrop offers a PreWatch function to see the result before converting. It could be a long way of Trail & Error to find the right value !
Distorted Sound ? Sorry, i didn't know how to solve this second problem.
rgrds, lca77