how about trying one of the couch to 5k plans

being able to run a 5k in 30 mins gives an excellent level of fitness for normal person and is an achievable goal imo, it is also easily workable into most peoples lifestyles 2-3 times a week

there are a few about

http://www.coolrunning.com/engine/2/2_3/181.shtml

http://www.c25k.com/

my oh is doing this one which has mp3 downloads for each lesson

http://www.nhs.uk/LiveWell/c25k/Pages/couch-to-5k.aspx