Spotify not playing songs at all

I've searched for help from this forum, but in vain. Nothing have solved my problem about why my Spotify isn't working. :( So please if you could help me.

The problem is with the songs. I manage logging in and even downloading the playlists (that are the main problem now according to the Spotify service status thingy), but when I'm starting to play a song, it doesn't work. Either it starts and lags within the next few seconds or it doesn't start at all and jumps to the next song (which does not work either, fyi). I've tried uninstalling, re-installing, booting my laptop, deleting the Spotify and re-downloading it. I've changed my Spotify settings - some of the solutions suggested that changing the Cache size would work... well it didn't. Neither did changing the Proxy from auto-detect to no proxy. Unchecking the 'Enable hardware acceleration' did nothing to this matter either.

And that's not all. My Spotify keeps telling me that I have some sort of a problem with my sound card; impossible, since I checked it yesterday and it said that there are no new updates available for my sound card. Again I tried everything I could find in this forum, but the problem still lingers. It's getting VERY frustrating, since I'm a premium member and the whole thing won't work. Have I paid for nothing? :(

my laptop info:
Sony VAIO
Windows Vista Home Premium, 32-bit
Wireless internet, 54,0 Mpbs
sound card:
Realtek High Definition Audio
spotify username: lovelyapper