97 VW Jetta GLS swerve to the right

When driving my jetta I can't go no faster than 50mph and when changing gears or braking my jetta will swerve to the right unexpectaly. Also When changing from second to third or going into neutral and braking the right front side grinds. The problem is all on the right front side of my car. I have changed the brake pads and the rotor, I was told about checking my bearing's and something else but I don't even know where to locate it. Can you please tell me where to locate the problem and what could cause this problem and what are my options. So far I have changed my serpentine belt, starter and alternator. I have been having problems whenever I would fix something else and my engine light will not go off. I am scared that I may have a accident because my car swerves to the right as if my tires lock. Please whatever information you may have about my problems I would greatly appreciate any feed back.