noob; Should I update my OS?

It's up to you. I'm also using 10.5.8 and I have no immediate plans to upgrade to Lion. My Mac still does everything that I need it to do, and it's "snappy" enough for me, so I have no compelling reason to "improve" it. My current plan is to upgrade the OS when this Mac (only four years old) dies and I have to buy a new one.

 

I think it's worth the money to go to Snow Leopard. Apple removed a lot of cold code from Leopard and Snow Leopard is a little more robust. I don't see the immediate need for Lion unless there is a feature you need/want.

 

Lion is now 4 years old and is a legacy OS - there have been no security updates for years.....

Please update to Snow Leopard - your MacBook will run quicker and you will gain some hard disc space too....

Frightening really........

 

You mean Leopard, I think.
It's a Mac. Security updates?

 

Do you mean security updates like: Security Update 2011-004 (Leopard) released on June 23, 2011?

 

Security updates are only available for the two most recent OS versions. Leopard stopped being updated when Lion was released in July 2011.

So far, that means Leopard never got Security Updates 2011-005 and 2011-006, or Safari 5.1.1. It will also not be updated for any future bugs that are found.

Also, Java on Leopard is stuck at 1.6.0_26, which has bugs "which may allow an untrusted Java applet to execute arbitrary code outside the Java sandbox." (If nothing else, I'd suggest disabling Java applets in your browser if you're still running Leopard.)

 

I recommend disabling Java in any browser, unless you're at a trusted site that needs it. This is regardless of which OS or which Java version you have.

 

Would that include Java Script as well? What effect will that have that I will notice?

 

No, just Java. It's fine to leave JavaScript enabled. You won't notice Java being disabled on most sites you visit. If you visit a trusted site and a form or other function doesn't work properly, you can enable it while visiting that site.

 

Thanks. I had disabled both, but then my wife's work e-mail gave an error message in which the word "script" was lurking. I'll try just Java tonight.

 

What would Java do in the browser? I can find it in Safari, but not in Chrome. Is it safe to use Chrome?

 

Having Java enabled creates a malware vulnerability. For details, read the last part of this section of the Mac Virus/Malware FAQ

 

Thanks for the link. I thought those things could not get hands on Mac. I have disabled the Java in Safari.

 

Malware, sure. A virus, no.

 

noob; Should I update my OS?

I think you'd better update your OS, the newest Lion is better than Leopard or Snow Leopard in many aspects.