Watching page outs over a given period of time will let you know if you need more RAM. The best setup is to have it so that you have nearly zero page outs.
269MB isn't a high number if that's for a long period but if that's after 1-2 days without a reboot, it could be worth upgrading. Type uptime into a terminal and hit return to see how long your computer has gone without a reboot when testing.
4-8GB is fine for basic apps like Safari, Word, Mail and so on and moderately productive work.
16GB is better if you do anything productive with the Adobe CS Suite, Final Cut, Aperture and so on. Also if you use virtual machines like Parallels or VMWare. Apps that can use 2GB+ real RAM each.
32GB is overkill for most things. If you run apps like Mudbox or ZBrush or image editing apps with high resolution images, the apps can use 4-10GB of RAM each so if you had multiple of these programs open, you can run out of 16GB.
There is a guide here for what the terms mean:
Wired is memory used by the system e.g kernel/root processes. You don't get much control over this and I feel it should be lower than it commonly is.
Active is real RAM used by your apps - use the real RAM column in the Activity Monitor to see the heaviest apps.
Inactive is cached memory that helps load apps back up quickly. Apps will take longer to load after a cold boot than if you just quit and relaunch.
Free is obviously whatever is left.
Page In amount is data moved into RAM, When an application loads, it copies the program into RAM and associated resources so that number keeps going up all the time. It's hard to tell from that number how much paged out data has been moved back into RAM so the most important number is Page Out.
Page Out amount is when you run out of RAM and data in RAM has to be pushed onto the hard drive. When it needs it back again, it'll increase Page Ins.
Sometimes a lot of inactive memory allocated can affect performance but it can be flushed by typing purge into the terminal and hitting return. The blue block should almost entirely disappear after that but it should only be needed if the blue block is excessive.