The former question is a classic issue of thermodynamic vs rate product. However in this case the rate product is also the thermodynamic product...I'm pretty sure.
The reaction for the former can either be a 2,3 adduct or 2,5 adduct. Your Organic book should have a section devoted to this subject.
For the radical reaction, transfer of radical character occurs with the addition of bromine and thus the most stable product will occur when the radical is on the most stable carbon; and thus bromine will add to the less stable carbon in relevance to its degree of substitution.
the initial addiction is a electrophilic addition to the alkene.
Bromine is the electrophile in the latter and a nucleophile in the former. The former has a resonance stabilized intermediate. The latter is a anti-markovnikov product. You should keep on looking for other differences.