Thanks, is there any sort of software that'll keep it at peak performance?
There is no substitute for good habits. Anti-virus software, don't visit some kind of websites (you know what I mean), regularly defragment your hard drive, try and reboot it at least once every two days, use various software to assess the state of your components (like use the windows memory checker to check for memory errors, use HDTune or whatever to see if your hard drive isn't failing, etc...), etc... Basic maintenance really, and your laptop will last for years.
I second Buwish, adding an SSD will dramatically improve your laptop's performance. Specifically, it will decrease boot time by orders of magnitude and will reduce loading times (like in games, or even when opening applications and saving files). But an SSD is very, very expensive - 80GB is about $300 right now for laptops and the cost is linear in storage size.
More RAM will likely make no difference if you already have 3-4GB in it. If not, I would personally add more memory to reach 4 gigabytes, I mean memory is so cheap these days and your motherboard most likely supports up to 4GB, it would be stupid not to.
But what I would personally do is save the money for a desktop build, and then include the SSD in that computer - as a result your laptop will remain the same, but you'll get one beast of a gaming rig. But it depends on how you use your laptop, this is just a suggestion.