Thank you all for your tips and advice!
The only things that were left behind when we moved in were the curtains and some rubbish under the house (nice!).
As far as strange 'sounds' are concerned there really haven't been any... unless you count the bloody possums scampering over the roof all night - took a while to get used to that clatter! (and no, before you ask they don't rattle loudly enough to effect the doors).
Hubby and I both work odd hours so I'm often home on my own and wouldn't say that I'm afraid to be alone. It's happened many times when he has been home happily engaged in the playstaion or doing the laundry (personally, I prefer him to be doing the latter than watching for cupboard movement

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Hubby actually came home one night to find them all open but assumed that I was trying to make fun of the situation and laughed it off... still doesn't believe that I had no hand in the event. He has only seen two of the doors creep open on their own but thought nothing of it.
It can happen at any time day or night but more often than not happens in the mornings. Once I was in a frantic rush to get to work and had already closed all of the doors before walking away to brush my teeth - it was only moments later when I rushed back through, still with the toothbrush hanging out of my mouth, and found them ALL open again. The pestering thing is that if I'm home on my own, the very tall Hubby device is not in service and I therefore have to climb my short self up a chair -in heels- to close the top cupboards. While performing this very tricky balancing act and cursing through splatters of toothpaste, I was climbing down ever so elegantly when only the top cupboard opened again. I hadn't even dragged the chair back to the dining room. I think that this was the first time I actually thought more into it because it was as though something was toying with me on purpose, not just the 'breeze'.
I actually did have a bit of a mimi tanti at this and yelled out 'Seriously, this is not funny I'm late and tired just bugger off' and after that there was no more openings that morning.
Still happens months later though!
As boring as it sounds there really is nothing else weird that happens other than the doors opening. Has anyone seen the Sixth Sense when Toni Collette walks back into the kitchen to find everything on a hinge open??? It's just like that only we don't have a scary psychic child who can see dead people - not that I'm currently aware of anyway. So far the only strange things our two year old sees regulary are the Wiggles. (Are they just an Australian thing?? I'm sure Aussie's will get that

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I think I will try to get a medium to come and have a gander at the place. Where does one find a genuine meduim though???