Any suggestion for my php project?

hi, all: We have a bioinformatic website that focus on experiment submission and data analysis. The old site was written in PHP. Now, we try to re-organize the website to make it easier to browser. One of the chanllenges is tracking the logged-in user's activity so that we can show which experiment, dataset, tool the user is using. Someone suggested PHPNUKE. I am not sure whether it can meet our tracking of user. In addition, we got tons of forms and pages. It might difficult to convert them. Would you please give us some good suggestion for some packages? It does not matter whether it is open source or not. Thanks. yours, xin