there are parks all over singapore - heck I'm currently living in dhoby ghaut and there are two around here (Mt emily and fort canning).
I'm looking to move out too and was wondering how much of a commute I could take after getting used to strolling to work...
From what I figure: Just get a place within 5-7 min walking from the MRT - preferably one which goes directly to your office with no changing trains and you'll be fine!