Windows Installation screwed up, now my iMac is screwedup

[blackbird123]

Hi,

so I was installing windows on to my imac, when i reached the part where the computer restarts itself, I forget what to do (i done this twice already) and clicked the option key, and went onto the windows installation disc. I continued to the installation screen where I saw the windows ultimate choice (me having home, I choose this) however when it got stuck at expanding files 0%, I turned the computer off. However this time when I turned on the computer, It takes me to a black screen with a blinking cursor a the top.

Any disc other than the windows installation one, get ejected when it reaches that point, and key commands (cmd r, etc) dont register even on wireless and wired keyboard.

My computer is out of warranty and is the mid 2010 model iMac

edit: eject disc with mouse button works

 

[Nermal]

Using your wired keyboard, hold Cmd-Opt-P-R at boot and keep holding until it has chimed twice (this can sometimes take 30-60 seconds). On the second chime, release Cmd, P and R but keep holding Opt and it should go into the startup manager. Once there, hopefully OS X will be listed.

 

[jav6454]

Do you press and hold the Option key as soon as the iMac starts? The OS X partition won't get damaged during a Windows installation (very unlikely) unless you format it by mistake.

 

[blackbird123]

Using your wired keyboard, hold Cmd-Opt-P-R at boot and keep holding until it has chimed twice (this can sometimes take 30-60 seconds). On the second chime, release Cmd, P and R but keep holding Opt and it should go into the startup manager. Once there, hopefully OS X will be listed.

Success, except I failed to hold option! (this can be easily solved )My gratitude can't be expressed in words! thanks so much! I was worried I had to get a new computer!