Ubuntu 13.04 shutdown problem. Got no idea what to do next

Ubuntu 13.04 shutdown problem. Got no idea what to do next

I have been using Ubuntu for two years now and had few actual problems. I
have searched this site and tried various things to no effect. I will do
my best to explain, and certainly include too much info as I have no idea
what my problem really is. Please take answers to the 'for dummies'-level
and I shall certainly do my best to understand!
So, I have this lovely acer TravelMate 5310 from around 07 that's causing
a bit of a headache. It's Vista was removed and replaced with Ubuntu 11.??
some two years ago and was updated to the 12.04 LTS at some point before
christmas. It has worked well except a problem with the network that's
solved with a plug in reciever. All was just fine until I two days ago
wanted to install the latest version, 13.04. I by accident installed
12.04LTS again and thought it won't matter. The problem with shutdown
started after this, and we have finally arrived at the point of all this.
It won't shut down. I removed the 12 and installed the 13 last night
thinking the problem might go away. It installed and updated and whent for
a restart without problems but came to a halt at the purple screen.
I performed the hard shutdown(the press button method) and restarted. It
boots up with ease and all is really well BUT it simply cannot shut down.
It now hangs on a black screen with loads of white numbers, words and
other such terminal-like things. So I push and hold shutdown to turn it
off.
I tried doing this Then tried the acpi=off in terminal but nothing works.
I have yet to try the command shutdown -h now but I now managed to hit esc
at the right time and go behind the first screen and see the next. I am
sorry that I have no pictures to show you.
The processes that seems to fail are two:
*killing all remaining processes.... [fail]
modem-manager[953] : Caught signal 15, shutting down...
then follows ok's on deactivating swanps, unmounting filesystems.
then:
*stopping remanining crypto discs... [ok]
*stopping early crypto discs... [fail]
Unmount: /run/lock: not mounted
unmount: /run/shm: not mounted
mount: / is busy
*will now halt
And that is where it hangs..
I hope you are able to understand anything. I have no idea. The formating
above is all wrong and such, I tried my best^^