I've been using slackware 13.37 for a while now and I have a separated partition for /home, but everytime I change distros, and i've done it quite a few times, I had always added the same user of the old one I was using.

Because of that my folder on /home is full with a bunch of configs and things like that from older distros and Desktop managers (from blackbox to unity, been through all of them) and everytime I try to delete some of those some error happens.

What I want to know is that if by formating my machine for slackware 14 now and deleting the old user folder, getting from it only the things I really dont want to miss like musics and codes I will have any problem?

I would suggest backing up the directtory to another drive or DVD's. Then install the new OS, configure to your preference. Then copy over any data and media files as well as any highly customized configs that are compatible. Like maybe cronta , anacrontab, bashrc or any other configuration files that are standard that you may have put some significant effort into. Otherwise I would just reconfigure as it will be cleaner.

Thanks for the help.
I guess my main problem is to figure out what of those config files are really nescessary.
Ok, I understand bashrc is something I need to take with me, but what about my .gitconfig and the .git folder, .ssh folder, .eclipse folder, .adobe, things like that...

Can I just, adding a new user, restart those things without having a headache later on? (and that are just a few examples :/)

Regarding the hidden configuration files, back up only the ones that you have modified. Any that you have left at default can be discarded. The new install will provide its own.

For example, in my case, I would back up my .fluxbox folder for my Fluxbox menus, themes, etc.; my .opera folder for my Opera settings, themes, and mail store (I use Opera mail as my primary mail client); my .pan2 folder for my Pan newsgroup settings; and so on.

In addition, I would back up my /etc/samba/smb.conf file, because it represents weeks of fine-tuning and my /etc/rc.d/rc.firewall script, and so on.