Which keyword should i pick ??

I have a keyword which has About 15,400,000 results

and another About 226,000,000

Which would be easier to rank for ?

the keyword " fish forum" has About 226,000,000

and the other keyword which has 15,400,000 i can;t mention because id get banned . Which would be better ??

You can't really tell the competition of a keyword by looking at the number of results. There are several other factors which have to be considered.

Those googel results don't make much impact on ranking. These are results not rankings.
You need to find the competition of your keyword. How many sites have your keyword in there title. etc., Search for fish forum get top 10 sites put that in to yahoo site explorer find out how many backlinks they have. If you can out rank them go for it. Better i advice you to read IamNRE's post http://www.blackhatworld.com/blackh...ethod-step-step-keyword-research-newbies.html
Hope it helps.