I can't open mkpg files

[CX1.0000:air]

Hey, I have Mac 10.4.11my problem is that I can't open mkpg files on my mac anymore. I cannot find my reboot cd. I don't have time or money go buy one. I was deleting a version of itunes from the main drive and it erased a different version I had on the other drive. Now I can't open mkpg to install itunes again. A few days ago I was clearing some stuff from the main drive for space. I don't know if I erased something I wasn't supposed to. I was trying to make room for stuff because it has 15 gigs and the mac itself uses 10 gigs and im left with like 4 left. I have an 80 gig in the computer as well but the mac system wont use it as a start up disk (that's not my problem at the moment). I emptied my trash thinking it was all good to be. I don't want to spend more money than I already did on buying stuff for it. I think it was something from Automator. I didnt delete it, I think I deleted some of its functions. I would appreciate all the help and advice I could get from you guys, thank you very much.

 

[VirtualTracy]

If double-clicking a .mpkg file has no effect, you may need to associate .mpkg files with Installer.

Here's how to do that:

Right/Ctrl - Click the .mpkg file and choose "Open With", then select "Installer".
If "Installer" is not listed under "Open With", choose "Other..." and browse to:

Applications ~> Utilties ~> Installer

Be sure to check the box for "Always open with".

You can also try dropping the .mpkg onto the Installer.app icon in your Dock (once it's launched) to see what happens ...

There's also a Terminal command you could try:

sudo installer -pkg R.mpkg -target /

Finally you can download iTunes as a .dmg, from here.