mysql/php

what i am needing exactly: a secure login page, for my chat system, the one i have now is not secure and i have had many sql injections through it, i need one that is secure, upon members logging in it should be able to start timing their session and for the "points". the "points" will be a members only virtual money system within my chat community, when a member logs in they would get lets say so many points every 5 minutes, this will need to be flexible where i can change the amount of points given out and the time limits. The points will accumulate into their members user accounts in a table on my pre-existing mysql database, they will need to access their points, a simple debit/credit, and update is all that is needed. They will need to be able to transfer any given amount of their points to another users account, example: my chat name- transfer my points to members chat name- amount of points to transfer- then it would credit/debit the accounts accordingly and then come up with the total that should be on a page, a leader board type, so it has the top say maybe 50 people who has the most points. (i dont have that many members but just incase). what i mean by points is that me and my members will use these points as a small simple virtual chat "banking" type system, it will not be real money but play type only. i have a database up and in place but no tables made yet for a money type system i can send you copies. thank you