2008 is not a model. Can you tell us the make and model of the laptop?
Generally: Editing videos can put a lot of stress on the CPU. Your CPU may need new thermal compound, and the fan(s) inside the computer may need cleaned, as well as the heat sink, if applicable (even if it's running better, these are things to consider on a laptop that is from 2008).
1 GB of RAM is not much to work with. 4 GB (or more, if possible) for Windows 7 would be much better, whether you are running the 32-bit or the 64-bit.