150 pixels isn't very big. How are you looking at it? At 100% zoom? Or greater?
Have you tried the anti-aliasing options in the options bar when entering the text?
Are you displaying it at 100% original size on the web?
It might be easier to judge what's wrong if you'd put a copy of the image up for all to see here. You can do that with the little "camera" icon on the web forum interface, just above the edit box where you type.
Thanks for help
I am using Myriad Pro, and yes i have tried the anti-alisaing options but they dont make much of an improvement.
I am not good with photoshop so maybe its very simple, or is it that an image this small, when viewed at 100% will always pixelate?
I have attatched an image below