Canasta Keeps Locking Up In The Middle Of A Game Wont Let Me Pick Up Discard Or

Sometimes if a room is almost full, people with an older system have problems like this. I'd suggest trying a room with only a few people in it to see if that helps any.  You can also clear your Java cache by clicking your start menu, control panel, Java, then on the Java control panel that pops up look on the bottom of the General Tab where it says Temporary Internet Files, click Settings, Then click Delete Files, and click OK.  That's assuming that they haven't embedded this game yet and changed it over to Flash.  You can go to the java.com website and click on the 'Do I have Java' link to see if you have the latest version installed.