It looks like a problem with the power to the laptop.
It is possible the AC adaptor is the issue, but try completing Step 3 above and make sure one of the items listed is not loading down the motherboard.
If you can get your hands...
If all your doing is web brousing, then the laptop will only use what resources you need, thus your loads on the CPU / GPU etc are low.
The power settings menu is good for configuring laptop settings for use on Battery Vs...
1. Test the battery by pushing the test button on the bottom of the battery see how many lights turn on
2. Does the battery charge indicator come on when the unit is plugged in.
3. Try removing the battery,CD ROM, hard Drive, Wireless...
Honestly Vista is a POS
Get Windows 7 and save the headaces.
but as far as your problem goes, it maybe the CD Drive is acting up on you.
if you have another computer and a 4GB USB flash drive you can make a bootable USB Windows...