can not re-install Ubuntu 10.10

I'm having a problem re-insatlling Ubuntu 10.10. It seems that the first complete installation of Ubuntu 10.10 was not complete, must have been missing some files. When I would boot up the whole system would flickers and the boot up audio file would studder. Then I tried to get on the system several days ago and the computer would not boot up, it got to the Ubuntu image and frost. I retried my installation disk but found the same , it would not boot and would freeze at the ubuntu image. I burned a new installation disk in hopes of possibly getting any missing files and tried to install from this new disk yesterday, no good,, now I get to the install page and it freezes. I tried an alternative cd, but the computer doesn't recognise it at all. The system partially works because it allows me to try Ubuntu which I'm using to type this in hopes of getting some help here.... I sure could use some help here.