is my acer aspire 5733 i3 duo core 4gb ram 500hdd any good for music production?

What audio software are you running? Some versions of some software is more CPU intensive than others. It should be fine, but will will have limitations in some areas, such as the amount of tracks and plugins it can handle.

im running windows 7 64bit,reason 5 its just that ive heared that these laptops are prone to breaking down after a certain time ive had a few issues with it but nothing magor except for the protools problem!.

Reason 5 runs well and isn't too CPU intensive until you start quite a few racks and effects. And with Protools you will just need to jump between different buffer settings till it works efficiently depending on if you are recording (lower buffer size) or playing back audio (higher buffer size).