You need a color wheel, Rood Dood
. By using the painting as a background, you severely limit your text color possiblities. You have 2 choices (to make text readable), lose the painting or only use contrasting colors for text. The painting is mostly greens and blues, therefore, yellow is your most likely candidate. Followed by white. Blue and green are both out. Red will tend to 'vibrate' on green or blue.
Yah...I got a college degree in this kinda crap
.
After reading MiniD's post, if you 'ghost' the background painting, your text color options will improve.