Choose one:

1. As root create a file named something like my.modules in /etc/sysconfig/modules which has the line; /sbin/modprobe ndiswrapper

2. As root crate a line entry in /etc/modprobe.conf which looks like:

alias wlan0 ndiswrapper

For either:
make sure you have a /etc/sysconfig/network-scripts/ifcfg-wlan0 file that looks something like;

TYPE=Wireless
DEVICE=wlan0
HWADDR=
BOOTPROTO=dhcp
GATEWAY=routers IP address here
DOMAIN=
ONBOOT=yes
ONHOTPLUG=no
USERCTL=yes
IPV6INIT=no
PEERDNS=no
ESSID=MyRouterNameHere
CHANNEL=1
MODE=Auto
RATE=Auto