[yuriyuri]

You should be able to get your thoughts across to them fairly well.
You will have trouble occasionally of course, but a year is a long time and you can learn a lot if you don't stop.

Of course having said that, if you can't/don't practise speaking Japanese then it doesn't matter how much you know, you will have trouble speaking.

It all just boils down to how you use your time.

If you practise speaking a lot but never read, then you will be able to speak but not read.
If you spend a lot of time studying grammar but not much vocab, then you may be able to put a sentence together well, but you will be limited in what you can talk about.
etc.

Anyway, the point is, if you study and practise a lot you should be able to have a basic conversation and you should be able to understand enough to get by.

From my experience I was able to have conversations over IM programs like MSN after a couple of months of study (I studied for at least 6 hours a day without fail to start with)
But I still suck at speaking even (roughly) 2 years on from starting my Japanese study, because I never really get to practise it.
(I mainly just have to read stuff out aloud to myself to practise my speaking at the moment... Which isn't ideal but it's better than nothing)