What version of King Arthur did you have when you were little? One Christmas my grandparents gave me this version of Malory illustrated with medieval paintings--I think they knew I was interested in Tolkien so they tried to find me something related and that's what they came up with :)
"The Boy's King Arthur", which is a slightly edited and abridged version of Malory's "history". Illustrated by N.C. Wyeth. The language is nicely archaic...and there's plenty of blood and guts. We wore out our copy rather quickly.
It has definitions in brackets for some of the REALLY tough or unusual words.