I have cable myself, I bought a Linksys router which both my PC's plug into, the router then goes to the cable modem, and there ya go. Added benefits to buying the router is a built in hardware firewall.
 
If your system requires software to use the modem, yes install it on both systems. My cable connection does not require any software, so I really don't have anything to compare to, I just plug in and I'm connected.

As Relic indicated, all you need is a router. Use only ethernet connections. Most computers today have ethernet connections. Under no circumstances use the usb connections. They may work for a while, but will drop out over time.
 
Plug your modem into the router and your computers into the router. While there is no hardbound rule, generally, turn your modem on first and let it synch, then, when it has acquired the isp, turn on the router and the computers.
 
One further note, while the router does act like a hardwire firewall, it really isn't. What it actually does is ignore any pings sent to it that was not initiated by your computer. In that sense it is a firewall, and this is an enormous convenience for your software firewall since so many machines out there on the net have been set up to ping addresses to gain access. You should also install a software firewall, anti-virus package, and a cookie controlling software.

Actually, my hardware firewall, built into my Linksys cable router, keeps me completely stealthed, just took a wee bit of tweaking, as in forwarding all port 113 requests into cyberspace.
 
For the record, from a grc.com scan, just a couple minutes ago:
 

----------------------------------------------------------------------
 
GRC Port Authority Report created on UTC: 2005-10-20 at 02:13:29
 
Results from scan of ports: 0-1055
 
0 Ports Open
0 Ports Closed
1056 Ports Stealth
---------------------
1056 Ports Tested
 
ALL PORTS tested were found to be: STEALTH.
 
TruStealth: PASSED - ALL tested ports were STEALTH,
- NO unsolicited packets were received,
- NO Ping reply (ICMP Echo) was received.
 
How is that not a firewall? Difference of opinion here, kinda splitting hairs, my firewall doesn't make noise, but blocks attempted probes. Software firewalls eat resources, block attempts at probes, make noise, and have very annoying popups. I setup my firewall, and it's done, no tweaking, allowing sites, nothing, aside from power-outages, it's been on for 3 years now. A good router, with a built in hardware firewall, pays for itself in less than a year. And it doesn't annoy the hell out of you.
 
I run anti-spyware/spam/virus/popup blocker/email protection, all free from rogers.com, my isp. I have absolutely no need for a software firewall.
 
On the otherhand, I do believe they are good for people who don't run an AVP or anti-spyware program, it will tell them when the virus is sending out packets, or the spyware is "phoning home". x) Yes, maybe a business with multiple idiots downloading all kinds of garbage have a use for a software firewall, but what is really needed is some educated employees, so they stop doing stupid things.
 
My wife and I sit here, both of our systems comfortably stealthed from probes. Black Ice? Been there, done that, wasn't as good as it said it was. Zone Alarm? Been there, done that, it drove me nuckin futz. Bought my router, $80, one shot deal, took me all of 2 minutes to stealth our systems, 3 years later, not a burp, paid for itself already.
 
BTW, anyone can configure their router to do the same, and anyone that would like instructions on how to do so, say the word.

Thanks for response. I assume router has modem built in as it connects direct to phone line then into back of computer(still learning know little about these modern day gadgets!)Unfortunately neither computer although only 3 years old, have ethernet connections, so only one is connected via usb.Broadband supposed to be 40 times faster but doesn't appear to be 40 times faster than dial up.

There are some modems out there that have routers built into them, NetGear does. You can also go out and buy a ethernet card for under 20 bucks and install it yourself.
I seriously doubt that you are getting the full broadband experience from using your USB connection.
Trust me you will see a huge difference between your dial up and broadband and wonder how you ever lived without broadband

I agree with cormac, get yourself an ethernet card, as low as $4. For $20, you can pick up a pair of decent ethernet cards and set up both systems. Here's a linky, but you can scoop an ethernnet card just about anywhere: http://www.tigerdirect.ca/applications/c...t=0&Recs=10
 
If you pick up a router, the connections are basically this: both PC's connect from the ethernet cards to the router. The router connects to the broadband modem. This puts the router between your two PC's and the broadband modem. If the router has a built in hardware firewall(most do nowadays), it protects both your PC's.
 
Test out your current speeds, and get a few recommendations on how to improve it at these sites:
 
http://www.dslreports.com/tools
 
http://www.speedguide.net/sg_tools.php
 
If you need any help with the tests, ask away.

Traffic Officer, if you decide to purchase the ethernet cards make sure that they come with Cat 5 network cables. You will need them to attach your ethernet card to either your router or modem.
One other option I forgot about, if you are unsure if you want to hook up a router, is to go with a hub setup. A hub is just a "glorified splitter". You willn't have the protection of a hard based firewall like you do with a router but hooking up a hub is real easy.
It is just modem out to hub or router in and then out from the hub or router to your ethernet card and that is it.
If you need any help with anything just let us know.

Heaven help me - more cables!Nice to know there are still helpful people in this world thanks.will try to put it all together at the weekend if I get my brain into gear.All this progress is supposed to make life easier-it just complicates mine.cables cards routers modems hubs ethernet usb or not to usb.I think I should have continued to live in the dark.Will announce if I succeed.