My pfsense box is now setup properly (i guess). I edited my original post.
I am now facing only one problem with the VLAN on the HP Procurve 2920 switch.
I do not know if may belong here but you might be able to help me :)
I have a default VLAN_DEFAULT with ID 1 on the switch with untagged ports 1-4,25-48. The pfsense box is connected to port 48.
Then i have the VLAN with ID 10 with untagged ports 5-24 for computers.
When i connect my laptop to port 1 for example, the default VLAN, i have internet and can ping all VLANs.
When i connect my laptop to port 5 however, i get an "unidentified network" with "no internet" on my laptop.
Do i have to add a NAT rule or similar on pfsense to get this working?