Rowing is a great way to do some full body
HIIT (High Intensity Interval Training).
Be sure to mix up your workouts on the erg though. Doing 2Ks will get boring very quickly and you won't see great improvements if those are all you are doing on the erg. Do some longer pieces at a lighter pace, and IF YOU ARE HEALTHY ENOUGH do some high intensity pieces with active rest such as 1 min on, 30 sec off, 2 min on, 1 min off, 500 meters on, 250 off. all these options can be programmed into the erg.
What version erg are you using? Is it a Concept 2 Model C, Concept 2 Model D or E. Models D and E have better programmable monitors.
I would suggest that you do some reading on here about diet changes and weight lifting as part of a weight loss routine. there's a lot of information to be had, and some very deep posts by our very own Chillen