2 Connections on 1 Computer

How is he directly connected now?  What plugs into his comptuer?  Ethernet cable?, serial cable? phone line?

point to point (serial) which goes from our main office to his home office.

Is there a CSU/DSU? or modem or router or what?

cisco router at both locations.  The router connects to a switch which connects to his computer.

You should be able use same router , to allow internet access.
If you can pass "show config" Cisco here , will be easier to understand.
In case of ISP- you can either add second IP set , to same NIC, or just add second NIC to PC , connected to ISP.

dons6718:
Agree.
It is easy enough to do , but he might start experience intermittent problem to the office LAN structure (depend on it IP schema).
Second NIC is $20 , and will provide more "cleaner" connection, not to screwing office LAN.
Either way should work, just depends on priority choice.

Here is the router config:
Current configuration : 593 bytes
!
version 12.2
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname Malibu
!
enable secret 5 $1$eKtN$QwwCgVNbtESDsRf39U.Mg0
!
ip subnet-zero
!
!
!
!
interface FastEthernet0
 ip address 192.168.7.1 255.255.255.0
 speed auto
!
interface Serial0
 ip address 10.1.x.x 255.255.255.0
!
router eigrp 120
 network 10.0.0.0
 network 192.168.7.0
 no auto-summary
 no eigrp log-neighbor-changes
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.x.x
no ip http server
!
!
!
line con 0
line aux 0
line vty 0 4
 password 7 14341A585F172F7A370F636526
 login
!
end

I am ordering a business cable connection for so he could use that for his internet surfing.  How would I configure his xp pc to use the point to point for his office stuff and the surfing for his web stuff?

Which is more reliable 2 nics or router config?

I would go with 2 NIC.
It will be more reliable as there is hardware/service are getting split, as well you can enable diffrent firewall setting for each NIC.
From Cisco config can really say, if there is an option to get on a web.
If this link is provided over internet, then would be no problem to enable access, as long the provider of the link will allow so.
With second NIC , you just connect it to the ISP modem/router, either by using same switch, or directly.
IP set will be given by ISP.

how will it differenciate between office work and web browsing?

This NIC's IP configuration will handle, no need to worry about.

Currently the router from his home office is connected to our corp router via point to point connection which is then connected to our cisco asa firewall.  The firewall has a default route setup so the home office can access the internet.

Ok so if I understand your correctly this is what needs to be done:
1. Remove the default route from the Cisco ASA.
2. Connect Cable router to same switch (switch A) that the cisco router connects to.
3. Install 2nd NIC on computer which also connects to switch A
4. Set TCP/IP config of 2nd switch to specs of cable router.

Is this right?  Do I need to do any other configs to the router(s) or NIC(s)?

No need to remove any routes.
Just add an additional NIC, and plug into ordered ISP modem/router(directly , or throught the switch)
Follow ISP instruction , to apply on second NIC, to allow internet access, and you all set.
Office LAN/router leave it as is.

OK.  I should leave the 1st NIC as is also?  I have someone scheduled to come out and put the new line in this week so I will let you guys know what comes out of it.

Thanks dkarpekin and dons6718.

Yes. You only add other NIC, and aplly config to it.
No problem.

I'm sorry but I have a question because I still don't understand how windows will know which NIC the specified traffic is supposed to go out of.  Can you or someone else explain the logic behind this?

Each NIC's will have Gateway IP, and their IP assign to it.
Routers - is Gateway  for those NIC's.
When you type in your broyser host name/IP address it will go out to the gateays- which would be your routers connected to your both NIC's.
From which ever router if will recive acknowledge where is this hostname/IP address is located, to that direction it will go.
Routers is a device , who handle connection between diffrents networks.And it is router job , to route traffic properly base on it routing table, and so on.
There is a whole network theory behind, and it's probably unpossible to explain in short notice.
But I can assure you , it will work fine.
If you so cirious, use following command in CMD, and use them on diffrent PC's:
ipconfig /all       - will show you IP configuration , of your network cards.
tracert x.x.x.x  - will show you how many routers/hops is on a way to destination.
ipconfig /release - release issued DHCP ip
ipconfig /renew  - will obtain IP again from available DHCP
Last 2 command usially helpfull, if your NIC freezed, or someother issue on network/PC.

P.S.
In XP, when you right click on network icon- you can use "repair" it will clear up freezing, and other network issue ,as well.

I understand what you are saying but since he can currently access the internet from his computer via the point to point  to our corp router and out the corp firewall how will it know not to use this connection?  Don't I need to configure the homeoffice router to point to the cable router as the default route and add the static IPs for our internal LAN?

Will both routers have to be on the same or different networks?

Than I'm lost right now, what the point having second/localy internet access?
I did assumed that internet access over point -to-point is limited , or denied.
If you want this PC have this-local dedicated access, than you can disable his corporate access.
If both is enabled , PC will use one of them, and regardless of loosing either of them, still will have access over one availble, without any additional reconfiguring.
NIC's can be on same subnet, as long they will not have same IP, but it is better have them on diffrent subnet, which I'm sure you can pic  any you want, due to the fact, that  local ISP router will be under your contol.

I don't want the 1st nic to have internet access at all.  I just want the second one to do all of the internet (web surfing tasks).  He currently can access the internet from the point to point with the current setup but I want to disable that.  

That can be easy disabled on corp routers, by denying access, base on his IP of NIC#1 facing point-to-point.
This is something have to be done, by people , who is handling corp. routers.
There is many way to do so, and will know what is most appropriate.

That idea was presented by
dons6718:
where is also no need for Linksys router.
Due to fact, that you set gateway PC as Linksys router, that PC will be limited only to 192.16.7.x CORP LAN  only.
If there is any other networks within corp LAN, it will not be accesible.But you saved $20 on NIC, reqardless of waisting on Lnksys, which is extra, in this case.

I gave him points for that comment.  and yes I would still need a linksys router.  The PC was not limited to the 192.168.7.x LAN only.  I have access to all of our internal LANs (via corp point to point router) and internet via linksys router.