Hello, I downloaded an ntfs systemfile from tuxera and used it to convert a usb stick, my imac froze a while after so I turned it off the on and now I have blue vertical lines on boot up and the a white screen with lots of tine blue symbols, need help

Hello, I downloaded an ntfs systemfile from tuxera and used it to convert a usb stick so I could put more than the fat32 4gb on, my Imac froze a while after so I turned it off the on and now I have blue vertical lines on boot up and the a white screen with lots of tine blue symbols after, mouse pointer moves but thats about it.

Have used R and cmd to get a menu up but once I choose one of the four options my mouse is rendered useless and I cant get any further, have downloaded, to another usb stick recovery disk assisstant and am trying to use that in conjunction with the lion option on the previously mentioned screen, computer was responding really slowly and has now frozen on the terms of software license agreement (maybe the last hurdle!) can anyone pleeeeeease help!!!!!??????