hardware or software or no clue???

Have an older HP pavilion...Celeron 1.7 ghz, 256mb, Intel 82845G/GL graphics controller.....problem...at different websites or even installed programs the text overlaps. It either takes the line above or below(not sure) and it appears on top of another line of text giving a garbled look. Also we are primarily using this cpu for a new program that we installed. It has an image of two hands...it then has check boxes that are supposed to be aligned on the fingertips...they have shifted/offset to one side. We initally had the program on another cpu and this was not a problem but my boss does not want it on her cpu only on this one. do not know if it is the older cpu...graphics or what...any ideas would be appreciated....thanks