You'll see there are a lot of similarities between Sweden and Finland.
Generally us Helsinkians speak good English, but there are some exceptions. If you run up to a jerk that doesn't speak the language well, don't stop trying, most of us do speak it well.
And as Finnpinn said, there are some nice workingclass places outside of the "imperial center" (yeah i know

) like Punavuori (<- maybe not nowadays a workingclass place) Kallio, Hakaniemi, Alppila etc. etc. those are the places you are going to see real Helsinkians.
But if you want to party it's better to stay in the real center.
Btw if you are using the metro (which i think you should, as then you'll be able to go to places faster and find maybe some places that are less known), i suggest that you should not go to any place eastern than Hakaniemi maybe. Believe me you don't want to.
If you want to do something different, try Yrjönkatu swimming hall. It's absolutely beautiful. Some people swim naked, but you are allowed to use swimming trunks aswell. There are different times for women and men.
Just in case you want to, costs only 4.60 euros. And it's owned by the Helsinki city so shouldn't be anything creepy.
Just to throw in something different.
