It's a 650 metre walk. As for times it's a wash.
https://maps.google.com.au/maps/ms?m...05857,0.009162
With checked luggage to carry definitely take the bus, without maybe a walk will freshen you up.
See this map - the Blue circles are where the A bus will stop.
(To be honest, two hours is quite a tight connection - I try to avoid anything under three hours.)
http://www.lawa.org/uploadedimages/l...es/GT_mapF.gif
Although, jackal's advice about any/all buses below is useful.