hazmat2727

Ok, i,ve owned a NetMD mz-ne410 and its been dropped so many times the screen doesnt work neither does the forward button. Well a buddy of mine gave me his old MZ-R500 Recording MD Walkman and when i plop a disc in ( I have tried numerous discs) it sounds like the disc is scrating or something unless i leave it on a very stable surface untill it reads the 40 seconds of the disc or watever for antiskip. then i can move it freely untill i change the song, oh ya and when i tilt it vertically the disc will start to scrape or watever if its still spinning the disc. Has anyone had this problem befor or know what is causing it? Im sure i'd have to take it in but I would atleast like to know what is wrong with it. Any advice would be much appreciated.