If you have a multi-user subscription, you should be able to load it onto other computers at any time during the period of the subscription, and the clock starts ticking when you load the first one on. I have a 3-user subscription to Norton anti-virus and I loaded one right away, and another 6 months later. However, I have the disc. Since you downloaded yours, did you save the program on the first computer? If so, you could make a copy on a flash drive, and plug that into your netbook and install it. If you don't have that option, you should go go the Symantec web site. When you put the program on the first computer, there is typically a registration step that establishes an account at Symantec. Each time the program is installed and registered, the registration process takes you to the web site and the number of program installs is kept track of in your account. If you log into this account right now, it should show that you have two installs left of what you bought.

If you don't have the program, and/or you can't remember how to get into your account (or can't retrieve the info), call Symantec tech support and explain the problem and they should be able to walk you through this. It would probably be helpful if you had your online receipt of the purchase handy when you do this.

Avast is probably the most recommend software on security type forums, because it's free, small footprint, and it works. I take it it's a Windows 7 machine so you can use the firewall built in.

I would add (Wot) Web of trust software, You can Google that. Also I would add spywareblaster that program prevents malware.

Since the kids will be using the computer install Ccleaner and run it once a week. Install Malwarebytes update it an run it once a week as it does not run in the background.

Another Anti Virus to consider is Microsoft Security Essentials, low foot print.

Here is a link that might be useful: avast.com/free

The first thing I would do is make them separate user accounts and not give them any admin rights at all give them basic user accounts. Do not give them your admin password and make it a hard one they can not guess. this is for everyones protection.

I use AVAST free on mine along with malwarebytes free and superantispyware free, update and run full scans with both once a week or so, put spywareblaster on it as zep recommended also. I would put firefox browser on it for them to use and put WOT on both browsers.

SUPERAntiSpyware Free Edition
How to download and install Malwarebytes' Anti-Malware application for Windows computers
SpywareBlaster no scans to do but you do have to open it weekly hit the update button then hit the enable all protection so the shield is green.
Safe Browsing tool WOT Web of Trust put it on all browsers you use and know not to go to any RED sites.

A related question: should I be using Microsoft's built in firewall on my Win 7 netbook? I'm using Zone Alarm free.

Plus everything else recommended in this thread but WOT because we have no children.

I have no children using my pc either but I have WOT on all of them it is protection we all need especially if you use google searches very much or any search engine for that matter. It is an excellent addition to any pc. It even lets you know if links in your emails are safe or not.

You can use the windows 7 firewall or zone alarm. if you have zone alarm on it then I would just continue on with it but make sure the windows 7 one is turned off, only one can be running.

Buyorsell wrote - A related question: should I be using Microsoft's built in firewall on my Win 7 netbook?

There is no need of an additional or replacement firewall with Win 7. The one from MS is a 2 way and does the job, your choice of course.

I have no children using my computer either, but I would not be without WOT. It lets you know if any sites are not safe.

Thanks everyone for all your comments advice ext..

I was able to figure out the Norton's issue and installed it on my Dell mini..It actually downloaded the new version of Norton 360 version 4. I like it much better than the version 2 I have on my HP Laptop..

I did make everyone separate user accounts and Norton has a ad-on for watching what kids are doing and is filtered by their age too..Not sure how good it is but its better than nothing I would hope anyway..

I plan to check out some of the other suggestions mentioned above..

BTW, the Dell was a refurbished one from Dell Outlet and so it has the older Windows XP Home with service pack 3 rather than the windows 7..Which is sort of what I wanted as I know XP as I have not tried 7 yet..I figure I would rather have a little older version as the kids I am sure will get some things that they will need fixed on it....

Thanks Again for all the comments,
Kevin