Software :: On Internet Screen Not Display Certain Characters Or Text Boxes

When I am on the internet sometimes my screen will not display certain characters or text boxes. When I was on a website the other day I was attempting to input some information and the screen would not display what I was typing or what would appear in the drop down boxes. And I have had this problem on several websites, but when I use a different computer it works just fine! I can't think of anything to do! I don't know what you may need to know about my computer but here is some information:

Model Name:MacBook Pro
Model Identifier:MacBookPro3,1
Processor Name:Intel Core 2 Duo
Processor Speed:2.2 GHz
Number Of Processors:1
Total Number Of Cores:2
L2 Cache:4 MB
Memory:2 GB
Bus Speed:800 MHz
Boot ROM Version:MBP31.0070.B05
SMC Version:1.16f10