How will I connect multiple computers through my home LAN using HPNA, wireless or any other router?
Most LAN devices now do built in PPPoE, or you can pass the PPPoE right through software right through them.

I have a LAN and my client computers have trouble with Web Browsing, stalling, sending large e-mail's, etc.
You probably need to change the value for your MTU on the PCs being affected/ Download one of the programs below to the affected computer, set the MTU for your Ethernet card to match the MTU of your server.
You can try DrTCP

If your problem is only with one PC and you don’t have a network adjust the MTU value to 1452 in your PPPoE software.

How do I determine what MTU packet size I should use?
In a DOS Prompt type (Start Menu -> Run -> Type "command" -> Click "OK")
ping -f -l [packetsize] [www.yourisp.com][packetsize] = the amount of data you want to send under 1500
[www.yourisp.com] is your ISP's URL The largest value that does not give you the error "Packet needs to be fragmented, but DF set" take that value and + 28 (to not exceed 1492) and make that your MTU.
Note: also Set the default receive window to be (MTUValue - 40)*128

1) Install an Ethernet card in each computer and a second one in the server to connect to your DSL modem.
2) If using Win 95, 98, or ME as the server assign an internal IP to each each Ethernet card (For the card connecting to the modem use an address of 10.0.0.xxx and for the card in each PC use 192.168.xxx.xxx) use these instructions.
3) Make sure you use a cross over Ethernet cable between the two PCs and a straight through Ethernet cable to the modem.
4) If you are using XP or Windows 2000 as the server, do not set an internal IP address on the two Ethernet card that connect each computer, make sure they are assigned to use DHCP.

1) Install an Ethernet card in each computer.
2) If using Win 95, 98, or ME as the server assign an internal IP to each each Ethernet card use these instructions.
3) Use straight through Ethernet cables for all connections if plugging your modem in to the uplink port on your hub. If you do not have an uplink port please use a cross over Ethernet cable.

Note: For the above method use straight through Ethernet cables for all connections.