well i went in about 15mins but thats coz they let me do everything first coz i was missing my physics course... but it takes about an hour, but can b made faster if u turn up about 1/2 an hour b4 ur due (so ur first in line), get the little hecs book early (its on the enrolling desk thingy) and fill in as much as u can on the 2 sheets in there, and the only wait then is in queues of ppl who didnt even know they had 2 choose subjects. its not really hard or confusing, ull b fine... hehehe i thought it was fun
oh yea, and parents are definitely allowed, most ppl had a parent when i went (i walked past all the engineering ppl and did mine)