Thank you Sopa.
So, BTC-Core is reading the wallet.dat file incorrectly because its a QuarkCoin wallet. Odd, but a good explanation.
I'm pretty confused as I dont remember doing this but I can't argue with results.
Sadly 4,000 QRK are virtually worthless nowadays. I guess this can be a good lesson to anyone looking at altcoins. I'll see if I can sell them but for such a small amount I'd guess that the fees will make it not worth it.
I'm still going to hunt around on my PC for any other wallets. I know for certain I had some BTC. Though I have a sinking feeling that they were stupidly left on BTC-E a long time ago.
If I do manage to get anything Sopa I'll be sure to send you a thank you.