Take a look at these:

26281 apache 14 0 9336 9328 8820 R 8.7 0.9 72:14 httpd
28038 apache 14 0 9276 9268 8912 R 8.7 0.9 69:01 httpd
31474 apache 14 0 9340 9332 8924 R 8.7 0.9 49:14 httpd
31475 apache 14 0 9260 9236 8944 R 8.7 0.8 49:14 httpd
31476 apache 14 0 9264 9252 8920 R 8.7 0.8 49:14 httpd
2083 apache 14 0 9260 9252 8968 R 8.7 0.8 39:37 httpd
2084 apache 14 0 9276 9216 8904 R 8.7 0.8 39:37 httpd
645 apache 14 0 9428 9424 8872 R 7.8 0.9 44:01 httpd

They just won't die.
When I kill one of them apache stops :(
What is wrong?

Proberbly thier all from people visiting your site.

1. I don' think someone would stay more than an hour on my sites.
2. I don't want him to stay this long.

If that is the problem why apache stops when I kill one of those processes?

Why would you want to kill those processes? They're supposed to be there. If you want to change that, check your httpd.conf for something like:

#
# Server-pool size regulation. Rather than making you guess how many
# server processes you need, Apache dynamically adapts to the load it
# sees --- that is, it tries to maintain enough server processes to
# handle the current load, plus a few spare servers to handle transient
# load spikes (e.g., multiple simultaneous requests from a single
# Netscape browser).
#
# It does this by periodically checking how many servers are waiting
# for a request. If there are fewer than MinSpareServers, it creates
# a new spare. If there are more than MaxSpareServers, some of the
# spares die off. The default values are probably OK for most sites.
#
MinSpareServers 5
MaxSpareServers 10

#
# Number of servers to start initially --- should be a reasonable ballpark
# figure.
#
StartServers 5