As I understand it, you should be ok with the old notebook, as it is only going to be used as a display device. The hard work is done by the GPS receiver. It would be a good idea to Google up the sys requirements for any particular piece of software tough.
The MS Anto Spyware Beta is freely available and I have used it for months. I am one of its' great fans, as in addition to its primary function, it offers some very good system start up facilities which provide some really useful information.
Conan