I need to learn a second instrument

I want to study Music at University, likely abroad, since the tuition fees have gone up to such an extent that I've been put off of studying in the UK. I already play the piano, and sort of sing. I don't like my voice, and I'm nowhere near confident enough to sing in front of people. I'm a shower singer. I pretty sure that I'm more likely to get a place in a Music course if I can play more than just the piano.... so which instrument should I learn?

I'm pretty certain Jack could teach me to play the guitar. I quite like the sound of guitars... classical guitars, that is. Acoustic ones. Electric guitars remind me too much of 'it'. Thing is, they're portable, and particularly acoustic/classical guitars, don't weigh a lot, so that's a big selling point for me, who spends most of my school life on a train. Not quite sure what Mum would say to me learning the guitar, since 'it' also played the guitar, but Jack's a classical guitarist, not a rock guitarist, and that's what I'd be too. They're completely different.

I've considered the Oboe as well, as an alternative. They're interesting, not a lot of people play them (in comparison to say, the Flute or the Guitar or the Piano...) and it sounds nice. When you can play it properly. I'm sure that when you learn to play, the Oboe can sound pretty horrendous...

Hmm.... how about the Flute? Or... the Cello?

Hmm... maybe the Cello's a bit unlikely, as it's so HUGE and impossible to carry around. Forget the Cello.

Oh, I don't know!!! It needs to be something easy enough for me to be able to get to a good enough standard by the time I start University in 2012. A guitar looks really complicated, cos you need to remember where each note is on the fretboard and which string to play and so on... whereas with the Oboe or the Flute (I think) there is only one key combination for any particular note, so at the moment they're looking like more plausible options to learn to a decent enough standard by whenever...

But I might take a gap year and start in 2013..... I don't know..... SOMEONE HELP ME!!!!!!!