Go a hybrid as above but look for a 700C size wheelset as this will allow you to hold a bit more speed as you explore further With cycling i have found there is no in between you will either buy it and it will gather dust or you become an addict like myself and the bike goe everywhere
I am currently on a Scott Sportster 30 as a commuter and it is a good crossover bike
Couple of tips
Spend a little more for 1000 you will get an OK bike but bottom of the rung components which will wear quickly so you will find down the track that when it comes to chasing components to replace they are worth more than the sum of the bike so in 4 years you have ended up buying 2 bikes when you could have spent the extra on a good bike
Disk brakes are great but spend the extra to get a hydraulic system much more processive
Shy shorts are your friend they are like boardshorts with the lycra padding inside you will love them
This is what i commute on at the moment about 80k a week and i find it quite comfortable
It becomes then adictive see below touring ayres rock
The you do something you would never have thought you could like ride around the bay in Melbourne 200km
The you start doing crazy stuff like Melbournes famous 1 in 20 hill climb
but lets be honest this is the real reason i ride a bike