why are you trying to save string data into an INT field?
Yes, you can change the collation. Look in the [Operations] tab. You can change the DB's default charsets and collation, also.
I always specify them when creating the table, so this is never a problem:
CREATE TABLE IF NOT EXISTS `tablename`(
`id` INT(11) UNSIGNED NOT NULL AUTO_INCREMENT
) DEFAULT CHARSET=utf8;
# while setting the defaults for your whole DB is a good idea
# (and setting it to utf8 is an even better idea!),
# setting it explicitly when you create the tables makes your code more portable.
# you can specify a default collation also,
# however, mysql will automatically use the default collation for the specified charset,
# so it's not really necessary unless you want a particular, off-the-wall collation.