Which one should i get

try soaking the Disk in warm soapy water and try it off with a clean towl , if not try checking your xbox settings. If it donsn't work your Halo 3 game is stuffed , try buying a new one (Halo is aweasome :)

take your disc to a video shop and pay them to renew it shouldn't cost much or go to a second hand shop that sells it buy it and put your disc back in and tell them it didnt work swap money back ha

This can be caused by a dirty laser in the drive. try cleaning the laser with a q-tip and rubbing alcohol. If this does not fix the problem you will need to get the laser replaced. If it is still under warranty contact Micorsoft with this site: http://support.xbox.com/support/en/us/nxe/LiveIDSignIn.aspx?redirectUrl=http://support.xbox.com/support/en/us/nxe/registerdevice.aspx?step=repair

it means the one that wont read is scratched, dirty or defective, my advice is to clean it if its dirty, get a cd repair kit if its scratched or take it back if its defective.

my halo sometimes does the same thing when i start up the game but pressing a usually gets you through it, but if your xbox 360 overheats within minutes and is an older xbox 360 its usually a burnt out fan or just full of dust, if its old then ur warranty might already be out and if it is just open up the xbox and use an air compressor or anything else to get all the dust out of the xbox. in my case everything was just caked with dust. anyways... good luck
-Armand M.

cd drive error, if its an older xbox thats what it would be, either that or disk read error thing, i would suggest taking it in somewhere and have people look at it. or check the xox 360 games to see if there are any big scratches. that would be a big problem if there r scratches.

Unfortunately , a new xbox360 game cant be played in a normal xbox (not xbox 360)

The problem is that the new xbox is way different on the inside than the original xbox is. Because it is way more powerful, you can put an old xbox game into a 360, and it will work fine (most of the time), but if you try the reverse there is no way to make it work.

your internet

Call 1-800-4MY-XBOX and they will solve your problem. 

Is the disc warm? Let it cool off or maybe its because the disc is scratched which means you need to fix it.