This is a reasonably hard question..
I began considering this by thinking about future usage.. so that as illustrator may be the boss.. neither of those wouldnt be bad walking gemstones to begin making use of your regular Illustrator.
And these two have easy UI.
Suggestion 1.
Pixlr web editor is completely free and creates almost any internet browser which has expensive support.
It's nearly the same as Illustrator. Really it is similar to illustrator, it is simply missing some features..
For me the UI is quite simple ( though my looking of standard illustrator might cloud my judgement ) Its much more colorful and because it is missing stuff that say Illustrator cs5 has.. its causes it to be a great deal simpler to check out.
Additionally, it includes a number of languages.. unsure if that's bad or good as for me british is better to make use of with programs such as this.
Suggestion 2.
I wouldnt normally suggest Illustrator Elements but, well the UI it's happening nowadays is quite people friendly I believe. It may be good beginning point too..
However your family Photoshop's will have much more lessons ( if you usually can improvise using these kind of things.. )
Suggestion 3.
I wasnt sure about adding this when i initially considered how easy it might be to visit from specific program to presenting Illustrator. But with regard to adding towards the question I transformed my thoughts.
I've only attempted this once and I am fairly sure theres lots of variations.. such as the hotkeys that we have no idea but think that they're quite different..