Resident Evil: End Of Umbrella is the beginning of three chapters in Resident Evil. Basically, the title says it all: it takes place with Leon Kennedy and the BSAA trying to stop Umbrella once and for all. Leon, Chris, Jill, and Sheva are breaking into a secret Umbrella headquarters. They get separated, and that's the point at which you pick your charachter.
Whoever you pick will change the storyline: if you pick Sheva, Jill dies; if you pick Jill, Leon dies; if you pick Leon, Chris dies; last but not least, if you pick Chris, Sheva dies. The storyline is that you play as Jill and Leon dies. As the player goes through the headquarters, fighting a shark, a second Yawn, and ultimately Tyrant T-1010. This is where the player dies, as the player Jill (or whoever you should play as) or Leon (or whoever your supporting person is) gets stabbed and dies. Once you kill Tyrant, the place blows up and Sheva, Jill, and Chris escape.
Same as RE4, except the player may change it to a 1st-person view if he or she desires.