That's quite good! That is a correct description of the game, yes--in the full game there would be graphics for the dice, which you could interact with (say, "move your mouse over a die to scoop it up, click to roll all scooped dice), and also a clock with limited time, but... then it wouldn't be a bad game. ;)
The theoretical highest score possible is 306: with six of a kind in each number's category (6*(1+2+3+4+5+6)), a two pair made of 5s and 6s, a full house made of two 5s and three 6s, and the highest-scoring chance roll (25: 6,6,5,4,3,1). (Plus the dice-independent small straight, large straight, and six-of-a-kind point values.)