knights vs bishops

hey everyone, im just an average player who loves this game... just had a recent discussion with a buddy i play with frequetly about the value of bishops vs knights.  i suppose i havnt studdied chess at all but does anyone have a good answer to which is more valuable?  and a good explanation for me

bishops in an open game, knights in a closed game/
knights in the opening, bishops nearer the end.
Also, a bishop pair is considered better than any other combination of two of them, since it's easiest/possible to mate with only them and the king, and they have the best control over the board.
Personally, I think a good positioned knight is also better than a good positioned bishop. Yet bishops can cover distances easier, knights can cover clusters.
According to different players alltogether a bishop is slightly more valuable. 
(3 for a knight, 3,5 for a bishop. I haven't found a good player claiming the opposite, i go for 3 for a knight 3 for a bishop) 

2 knights vs a queen is a draw, but 2 bishops vs a queen is a loss. That is because 2 knights can defend eachother but any other combination or minor pieces cannot.

A knight is better than a bishop in a closed position.

A bishop is better than a knight in an open position.

Two bishops are better than a knight in an open position, but not in a closed position.

And so forth...

Knight on the fourth rank is equal to a bishop. 

Knight on the fifth is better.

Knight on the sixth tortures your opponent.

Bishop support points are usually bad; they can't backtrack because of the pawn defenders.

Bishops can dominate knights.

Bishop is better in open board.

Knight is better in closed board.

Bishop pair is decidedly superior to knight pair in open board, but not as often closed.

Knight if supported by another piece or pawn on the sixth rank or on a strong outpost is an octopus on the board.

Bishop can waste a move, but not knight.

Bishop can cover two wings of the board at once, but not knight.

Bishop can trap knight that is on the edge of the board.

Two knights have better chances against a queen.

Two bishops can force checkmate, but not two knights.

Bishop can fork, pin, and skewer, but knight can only fork.

By the way I agree with hessmaster on giving the bishop a value of 3.5 points, and 3 for the knight.

In a must win game and most of the time, I always choose the bishop.