Computer corrupted?

Hello,
My sister has a major problem with her computer. She has an Intel core duo processor E4300 with Vista Home Premium which is 2 yrs old. She loaded a DVD for the grandchildren but didn't check if it was compatility with Vista (she now knows it wasn't!). Unfortunately this is what happened:

It appeared to load up okay then was informed to restart computer, this is where the problem started. It would go no further than the second screen i.e. before Windows logo? So she shut down using the power button, this time it started up again to second screen and then a new screen stated:

Windows Error Recovery
Windows failed to start
a recent software or hardware might be corrupt (guess we know that)
To fix:
1. insert disc or restart
2.choose language click next
3 click repair computer

She found what she thought was a recovery disc the correct one inserted it, light on as though reading, computer restarted and once again stopped. Tried again this time message was something like "if windows or power interrupted highlight one of the follows:
1. safe mode
2. safe mode command prompt
3. last known good configuration
4. safe mode network

She tried them all - no go. Safe mode only got to a page where she said it had a list of drivers on.

Computer kept rebooting but got nowhere.

There was power but then she said it was almost as if it ran out of breath and shutdown and started again.

She has checked all the wiring is okay and not loose or unplugged in any way.

Another site recommended downloading the Vista 32-bit recovery disc, which I have done for her but not close so need to post to her.

Any suggestions of what this could be. Have tried several times to get into safe mode but it just shuts down and repeats over.

Many thanks