I have been living a very unhealthy lifestyle in the past 5-6 years,sitting most of the time studying or watching TV,internet etc.I never paid any attention to what i was eating,i am a smoker and i always have 3-4 drinks in a week.I guess the only good physical trait that i have is a normal weight of 75kg with 183cm height.
Smoking definitely needs to go, but your alcohol intake not so bad. Apparently, men do quite well on 1.5-2 drinks per day. Take alcohol with food, however.
My advice--throw out your TV. Once you stop watching it, you won't miss it. And don't use the computer unless you are icing your joints or muscles after aikido practice and need to distract your mind...