As de dee wrote, look for the DOT Number on the tryres sidewall. Its a 4 digit code and it gives you exactely the productdate of the tyres.
For example DOT 4711 means:
47th week of the year 20
11 or .... eau de cologne....
Therefore it might well be that also your tyres are at least 3 years old or even older.
Which brand to replace with? Well, probably everything is better than these chinese/taiwanese Shing Zen or Kendas the scooter came with...
Michelin, or also Heidenau Tyres. Metzelers also good, but probably a bit soft with quick wear.
Heidenau is interesting because of the stiffer sidewalls and well balanced allround capabilities (wear/milage/wetriding/safety).