Cedar Point is great fun. It gets expensive if you eat there, so I'd avise packing a cooler and leaving it in the car trunk with LOTS of ice. Must ride coasters are:
Millenium Force: Last year,they had a "ticket system" in place, where you went through a queue and got a ticket for a certain time of the day to ride. Then you could get in line at that time. Dunno if they're doing that this year. I almost blacked out on this ride, so it's a good one

Mantis: Second best coaster there, decent sized line, but worth it
Raptor: Best coaster in the park. Wait the extra time to be in the front row
Magnum: Fairly high, fairly fast. Ride this one before millinum force, otherwise you'll be disappointed
Snake River Falls: You're going to get wet. Very very wet. Make sure you stop on the bridge to get even wetter.
Mean Streak: Really fun wooden coaster. If you're tall, remember, you're not going to hit your head. Repeat that to yourself
Ride em if the lines are short:
Thunder Canyon. Possibility to get very wet on this one, its all chance. Otherwise, its just a wet ass
Mine Ride: Don't let size fool you. It's some "Oh Sh!t" moments. This was the last coaster my Dad ever rode, it scared him so bad (there's one point where it looks like you're going to fly into the line of people waiting)

Iron Dragon: Good "training coaster" for people who might be afraid to try them. Sit in the front cart

Gemini: Another good training coaster. Fairly short
Rides to avoid:
Corkscrew: Really short, not much fun
White Water Landing: Going down a steep slope in a canoe with little keeping you in is fun, but you'll end up with only a wet ass.