problems networking two PC's through router

I have networked my two PC's via a router, but cannot get the internet working on both PC's, only the one directly connected to the router.

SYSTEM INFORMATION

PC 1
-running windows 98
-connected to the router via ethernet card
-IP configuration
--IP address is 198.162.1.100
--obtains IP address and DNS address automatically
--default gateway and DNS 192.168.1.1
--subnet mask 255.255.255.0

PC 2
-running windows me
-connected to router via ethernet card
-IP configuration
--IP address is 192.168.1.101
--obtains IP address and DNS address automatically
--default gateway and DNS 192.168.1.1
--subnet mask 255.255.255.0

a cable modem is also connected to the router.

PROBLEMS

-PC 1 can connect to the internet, access the network and PC 2's files, and ping PC 2
-PC2 cannot ping PC1
-PC 2 can intermittently access the network - the network is there, but most of the time when I click on the "entire network" icon, the computer freezes.
-PC 2 cannot access the internet.
-PC 2 cannot ping PC 1

We've tried everything to get PC 2 to be able to access the network and internet properly but nothing seems to work! Every now and then it will access the network, but often it will not, while PC 1 can access PC 2 fine.

I'd appreciate any advice,

thanks, Claire