Greetings pmazurkiewicz,
If you have RSTP configured but disabled on some ports as you described, It will prevent the RSTP BPDU from the peer device on the configured interface and also never transits such RSTP BPDU to the peer device. However, other BPDU's from STP, MSTP, or VSTP enabled device, will not be prevented by the above configuration, if you want to prevent those BPDU's you will have to use this configuration as well "set ethernet-switching-options bpdu-block interface ge-x/x/x drop"
For more information, refer to the following link:
http://www.juniper.net/techpubs/en_US/junos12.2/topics/task/configuration/spanning-trees-bpdu-block-cli.html#bpdu-block-drop
If this solves your problem, please mark this post as "Accepted Solution" so we can help others too.
If you consider that my input was helpful, giving me a kudos would make my day:)