So I was trying to install vmware on my computer (Ubuntu Feisty, 7.04) and while installing it, the window for the serial popped up as I was IMing somebody, so it automatically hit enter took me to a screen saying the key was not valid, so I hit back, and it stopped responding, I waited for about 10 minutes before force quitting it, but the add/remove was still running, and I tried ending the add/remove process and every time I restarted it the window for installing vmware was still there, unfortunately, it wasn't going anywhere as the dialog box with the installation questions wasn't there, so I restarted the computer, hoping that would put me back at square one and now I can't open my program manager or add/remove. Every time I try I get this message

E: dpkg was interrupted, you must manually run 'dpkg --configure -a' to correct the problem.
E: _cache->open() failed, please report.

Anybody got anything for me?

Yeah..you shouldn't kill apt/dpkg when it's doing something, it'll freak out the dark side of Debian's package manager. Anyway, do as it says:
or if it says it can't find dpkg, use /sbin/dpkg instead of just dpkg. After that, try if your add/remove works again

And now I know, and knowing is half the battle. Thanks for the help, it seems to be working so far. I'm still REALLY new to Linux and don't know much of what I'm doing, recommend me to a good Ubuntu tutorial site?