So, this all started a couple of days ago when I tried to download an application from the internet. It installed and asked me to restart my computer, so I did. However, it never turned on again. It would make the noise, go to the apple logo, and then start a loading bar which soon disappeared for the spinning wheel. Looking back now, what a rookie move it was to download something that was probably a dodgy app... I tried safe booting the computer - did nothing. I installed Lion on it a few months ago, so I did the option + restart. I tried to use disk utility but it 'couldn't unmount disk' so I tried to install Lion again with the other button. It is currently on 'Loading installation information' with a pinwheel. I do not currently have the OS X CD. I don't mind wiping my hard drive as I have a time machine back up on an external hard drive (not on me currently though) Please help, I need my computer for the new year of school to begin!