Can someone help me "Outline the problems that occur with DNA Replication and what the consequences of this might be"
There are proteins which track along DNA in search of mutations. Upon encountering a mutation, these proteins activate DNA repair mechanisms which correct the mistake. As with anything, this isn't 100% efficient and some mutations remain. Cells that have damaged DNA could potentially become cancerous. There are a few ways in which this can be prevented: the cell can undergo programmed cell death (apoptosis) or the cell can undergo cellular senescence, an irreversible process whereby a cell can no longer undergo mitosis. If all of these mechanisms fail, a cell could become cancerous.
Hopefully this helps.