I currently own a 13-inch, Aluminum MacBook from Late 2008. I bought the Macbook mainly for general use but have since started doing music production and I am wondering what I can and should upgrade. I was thinking I should upgrade my memory to 4GB and maybe the the actual OS but not 100%.

Also my Macbook seems to get very hot, would upgrading the memory help this?

Macbook Specs:
2.4Ghz Intel Core Duo Processor
2GB Memory
250 GB hard drive
Running Mac OS X 10.5.8

Any other suggestions on how I can improve my Macbook for music production would be appreciated.