I have a 15 year old samsung HT-Z310 5.1 home theatre system. I am intending to buy a new AV receiver and use these speakers and may add additional speakers. Have read some articles but still unsure if they would be compatible and what other considerations I need to be aware of. Any help is appreciated. Thanks.
You will be able to use the 4 satellites and center channel speaker but not the subwoofer.
HTS package systems have the sub amp built into the main unit.
AVRs never have an amp built in for the subwoofer. They assume you will use a self powered sub. The satellites you have a too small to use without a sub.
You could use a small amp board to power the passive sub but I would just get a self powered subwoofer as the first step in upgrading your speakers. Next would be to replace the front three speakers and the rears last.