pentax optio 50 problemS

hi,
pentax optio 50 (purchased recently) which is taking progressively worse
photos (now appear to be through a red filter (all settings)).
i have brought it back to the store and they said the settings were
wrong (i had put it to default to troubleshoot) and changed them ... it
continues to get worse....
there is a 1gb memory chip (put in by the camera store) the specs state
max = 512 mbs HOWEVER pentax said 1 gb is fine (i called pentax) (and
the store said to ignore the 512 max)
i have a kodak (4 years old) 1.3 megapixels which takes great photos
(inside and out) so i wonder whether there is a problem with the
camera, me or both?
any help is greatly hoped for and appreciated