Hey NeedMoDro,
Welcome to Tech-Forums!!!
The Antec P180 series are very quiet, from what I hear. They use fans with variable speeds, and separate the case into three chambers to reduce the heat. It also has no lights, like you wanted.
Here's some of them:
Newegg.com - Antec P182 Gun Metal Black 0.8mm cold rolled steel ATX Mid Tower Computer Case - Retail Newegg.com - Antec Performance One P180 Silver cold rolled steel ATX Mid Tower Computer Case - Retail Newegg.com - Antec Mini P180 Black Steel MicroATX Mini Tower Computer Case - Retail
Some quiet fans I would suggest though, are Scythe S-Flexes, Noctuas, and Yate Loons.
Other than using an air purifier, there are dust filters for fans. Like:
Fan Filters : Performance-PCs.com, ... sleeve it and they will come