cannot view some pictures

I am running XP with service pack 2. Windows Firewall & Norton system works. Am new to using all of these. I come from ME, AntiVir & no firewall. I thought I had all settings correct to allow me to play games (yahoo) ect...however yahoo & some other web sites, some pics cannot be viewed. I have read through the posts & tried all that I have found.I feel as though I'm just not getting all 3 lined up to work together. Really have no clue as to what I'm doing, but trying hard to understand. Help would be appreciated. Thanks

 

probablly need to get micromedia flash player....

 

thanks for responding, however I have been working on this right along and I fixed my problem. I thought I had Java but did not, or perhaps it just needed to be re-installed because as soon as i installed it I was up & going. Thanks for being here!