You want str replace, because performance-wise it's much cheaper and still fits your needs!
$title = str_replace( array( '\'', '"', ',' , ';', '<', '>' ), ' ', $rawtitle);
(Unless this is all about security and sql injection, in that case, I'd rather to go with a POSITIVE list of ALLOWED characters... even better, stick with tested, proven routines.)
Btw, since the OP talked about title-setting: I wouldn't replace special chars with nothing, but with a space. A superficious space is less of a problem than two words glued together...