What is best for photo quality I print off a lot of photo's and I'm undecided if I should go with the Stylus 980 with three coulour ink cartridge, printing @ 2880dpi or a photo quality lower dpi with five colour ink cartridge.

A 5-colour photo printer will always produce better photo prints than a 3-colour printer.
DPI is not that critical; my tests with Canon's BJC-8200 (1200dpi) and S800 (2400dpi) plus Epson's Stylus Photo 870 (1440dpi) and Stylus Photo 895 (2880dpi) show that there is very little difference in sharpness between the lower and higher res models.
If ultimate photo quality is not an issue, a good compromise between everyday document printing and photo printing would be a HP Photoret III-equipped printer. But if you're sensitive about photo quality - the Epson Stylus 895 is excellent value and the more expensive Canon S800 is ultimately the best in terms of photo quality.
Ian