Browsers are crashing my mac

I have an iMac 10.6.8 It's an older imac (5 years?) that I've updated to 10.6.8.
I had a problem before I updated where any browser I used would eventually cause the mac to hang up and force me to shut it down manually. After the update the problem stopped, but now it's back.

I just repaired disk permissions so maybe that will help.

Lastly, I noticed this message when repairing disk permissions: Warning: SUID file "System/Library/CoreServices/RemoteManagement/ARDAgent.app/Contents/MacOS/ARDAgent" has been modified and will not be repaired.

I know very little about the technical end of things so sorry if this is too vague.

Welcome to Mac-Forums..

You can ignore the permission problems with ARDAgent, that's of no consequence...

Which browsers have you tried and how quickly do they crash? Is it better or worse with certain sites, doing certain things like Flash videos or doesn't matter?

How much memory do you have? How much free space do you have?

If it's any browser and only browsers that cause this, I suspect it's the content causing the problem. Does this generally happen when viewing any one page in particular?

thank you. It doesn't appear to be site specific. As I mentioned I cleaned up permissions yesterday and haven't crashed yet. fingers crossed. g

I'm not at home so I can't check my Mac but it's a pretty clean machine. That is, there's not a lot on it and I think the memory is fine but I'll check. it usually crashes after ten to thirty minutes. I updated flash after updating my OS. I use Safari and Firefox primarily but tried Chrome last time I had this issue and that didn't see to help.