Both the 1996 and 2002 versions of Resident Evil contain a noticeable degree of roleplaying. A number of events in the game's plot determine and are determined by other elements of the game's progression, from how the supporting role will help the player; whether they live or die and how the game, itself ends.
Determining Jill's progression
Where to find Barry
|Was the Ceiling Trap triggered?|
|Jill alone with Forest||Jill and Barry find Forest|
As shown in the chart above, where and how Jill and Barry will meet depends around the ceiling trap. Were Jill to claim the shotgun early and unwittingly activate the trap, Barry will come to her rescue. When she investigates the east-wing balcony, she will be alone when discovering Forest Speyer's remains. However, if the ceiling trap was avoided (or, alternatively, the player decided to claim the Armor Key before claiming the shotgun at all), then she will discover Barry inspecting the body.
In versions of the game based around the 1996 original (therefore, excluding the GameCube and Wii-ports), Barry will meet Jill Valentine after her second battle with the Yawn. Descending down the pit, Barry will accidentally drop the rope and rush out of the room to search for another - he will return within a set time limit with a second rope, ready to pull you back out. If the player decides to continue their search by going further down, Barry's fate may be sealed.
Who goes first?
This is again unique to the pre-remake versions.
In the underground tunnels beneath the courtyard, Jill will develop trust issues regarding Barry, and will be confronted with a choice at one point - should she search the area first or Barry? This RP-element ties in with the previous, rope-based decision. If the player chose to wait for Barry and go first, he will survive to the end and the mansion will be destroyed in the game's ending.
If the player chose to continue searching, and then decided that Barry should go first, he will make it as far as the Tyrant activation, being sent away to the helipad by Wesker. As he has failed to achieve Jill's trust, he does not knock Wesker out. En route to the helipad, Barry will be discovered collapsed on the ground and dying. Because he was not with Jill earlier, the team has not decided to destroy the mansion.
Were the player to decide on varying options, such as leaving Barry after the Yawn fight and then chosing to go first in the underground, he will be found dying when Jill prepares to return to the surface.
Rescuing Chris Redfield from the prison cell determines the very end of the game. If Chris is not freed, the bomb will not be activated, and the mansion will not be destroyed.