How to know if a Wii game disc works properly?

How to know if a Wii game disc works properly?
So I've got a bunch of Wii games from my sister which she wouldn't play anymore, and I was thinking of selling them on ebay. But the thing is, some of those game discs have a lot of scratches on them.

How do I know that these games do work properly or not? I tried inserting them into Wii itself, and it did read them without any problems. But what about in-game time? Could a game stop working at some point while playing because of a scratch?






















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Of course a game can/will lock up if a part of the disk it accesses is unreadable. If your wii is hacked, you can copy the disk to hdd or mem card- if it copies fully it will probably play fine. Might consider a cleaning disk for your sister, or modding it and using a hdd