Q: Can I update OS X 10.4.11 to OS X 6

1GB is quite low. What model Macbook do you have? Check the Apple menu, About this Mac, click More Info and post the hardware model (eg Macbook 3,1)

Matt

If the computer is still working fine, I would give it a go!

You could get up to 2GB in that computer, so you'd need to buy 2 x 1GB RAM chips like these:

http://www.amazon.com/Crucial-PC2-5300-200-Pin-Notebook-CT2KIT12864AC667/dp/B000 FQ2JLW/ref=sr_1_1?s=pc&ie=UTF8&qid=1413899830&sr=1-1&keywords=200-pin+pc2-5300+6 67mhz+ddr2+so-dimm

You can buy 10.6.3 disks from Amazon or other online sources:

http://www.amazon.com/version-Leopard-computer-processor-required/dp/B001AMHWP8/ ref=sr_1_1?ie=UTF8&qid=1413899635&sr=8-1&keywords=snow+leopard

If you do the upgrade I would be inclined to erase the current hard drive and install 10.6 as a clean install. You're likely to have preferences and settings from 10.4 which may not be optimal.

Matt