Kazbah - ifit was me I would include the couch to 5kms as part of the power walk...but if you wanted to be extra good do both - just be careful not to overdo it at first as I find that I am really motivated for about 4 days then get sick of it if I try to do tooo much (but then again I am a verrrry lazy person)

I have a friend at work who also would like to lose 20kg and we are (hopefully) going to motivate each other - it is my first gym class tomorrow in about 4 years....wish me luck girls - if you do not see me for a while it is because I have hurt myself very badly