When you eat 100 g of basmati rice and take on 120 calories you've had a "meal/snack" that's 1.2 calories/g (calories per gram) in energy density. An avocado might be 136 grams in weight (without seed) and contain 227 calories. If you eat two avocados then you can calculate that (assuming these numbers are accurate) you've eaten 272 grams (136 g x 2) of avocados and taken on roughly 500 calories of energy. This ends up being an energy density of 1.8 calories/g. What this means is that you can eat 50% more rice (as opposed to avocados, by weight) for the same amount of energy intake. Or another way of thinking of it, if you're eating basmati rice you can eat 150% the weight of the avocados for the same energy intake.
The difference in fat intake will be 42 grams from the avocados and almost none from the rice.
I also hear often that fats and proteins are more filling than carbohydrates, but I can only say that that's something I've "heard". I don't know if the research is decisive on this topic.
Also, remember that there are many many different factors to this issue. Just to mention one when it comes to dieting, there's something called the "thermic effect of food" (also known by a number of other names, including "food-induced thermogenesis"). Basically everything you eat requires energy from your body to metabolize that food. You probably would have heard the factoid that eating celery makes your body burn more calories than are contained in the celery, making it a negative-calorie food. Leaving aside whether this is true or not, this is based on that idea of the thermic effect of food. The thermic effect of eating carbohydrates and fats that is reported will depend on which study you read, and will likely vary on the type of person (what body composition they have, age etc.) and the type of fat you're talking about.
As I said, there are many different factors, including psychological ones about what foods feel more filling to you, but one last one I'll mention is the fact that your two avocados will have about 18 grams of fiber as opposed to a maximum of 2 grams of fiber from the basmati rice. A generally accepted effect of dietary fiber, whether soluble or insoluble is that it:
Increases food volume without increasing caloric content to the same extent as digestible carbohydrates, providing satiety which may reduce appetite.
Dietary fiber - Effects of fiber intake (Wikipedia article)
Aids in achieving healthy weight. High-fiber foods tend to be more filling than low-fiber foods, so you're likely to eat less and stay satisfied longer.
Here is a good site where you can compare nutrition data of different foods. Just be careful when reading information because cooked and uncooked cereals, such as pasta and rice, have a difference of "about" three times in their values (can be more or less, depending how you cook it).