The movies no longer are made up of HARD polygons but smooth ones; not much different.
I '82 is good. They're the old weapons we all love like the flamethrowers etc... The new weapons are pretty cool too like the lasers and sattelite nuking.
The game runs well on a 400 mhz. Even though I just borrowed this game from my friend, I personally won't buy it because I like the old I '76 better (unlike Quake 2 that I bought after trying it at my friends house...). It has better one liners and poems by the man, Taurus.
I recommend you to buy this game if you're a real big fan of the I'76 series... but if you're looking for a landmark game, buy Half-Life.