I have a imagelist with 52 images of cards; the 0 image is the back of the card. I am displaying a random card in the computer's image box and the player's image box. But how can i make the computer understand what these cards are and which is higher??!!

There are literally thousands of ways to accomplish this.

One way off the top of my head is to organize the cards in your imagelist from lowest value to highest: for example, index 1 thru 4 would be the various dueces, and 5-8 would be the three's etc. When you assign the cards to a hand, keep track of the indices that were selected, and compare the respective values: indices 1 thru 4 would have a repsective value of 1, indices 5-8 would have a respective value of 2, and so on... The higher the respective value, the higher the card is...