The specs
HERE seem to suggest this model comes with 256MB. I don't know why properties say 222MB, but my guess is that your onboard video has reserved some of it.
Since you mention it, my system has 1024MB (2x512) but says only 1.00 GB in properties. Never really thought too deeply about that before.
Whatever the case, more RAM and a graphics card would be a nice addition to that setup in my opinion (although a graphics card means deciding whether your power supply is up to it).