Aliens is one of my most lived movies of all times. But if you plan on buying a copy of it, please, please make sure you are not buying the Director's Cut edition. The ones with 20 minutes added to it. Most of the additions are useless (or just plain bad) and spoil all the surprises the movie had in its first cut.

Many, many times I find that Director's Cut is just synonymous with "take the best cut and fill all the crap we did not think was worth it in the first place".