I'm sorry I just cant vote on this one. As with all contests, there are some good, some bad and most are perfectly plausable - to choose just 5 would have to come down to personal preference and that just not right imo. So I'm just going to do a run down and mini critique on each entry. No way could I pick 5 and then put them in order of who is best.
1. BobJones: Nice skintone, though a little flat. Iris is too flat and a little green around the edges - but not so much so that it looks like its supposed to be there. Strong streak of blue under the eyelid going across the whites of the eye. Grey Veins
2. CathyH: Very striking iris, a little too striking. Too much blue in the whites of the eye and in the shadow areas of the skin. Obvious attempt to vary skin colouration but a little too heavy-handed. Nice attempt to put colour into the eyebrows - very few did that.
3. Doug_Colwell: Lovely iris, great detail on the veins. Skin is a little too pink for my preference, very little difference in the colour of the inner rim and skin
4. Bart_Hickman: Iris is way too saturated - looks like a colour contacts commercial. Skintone is flat and the same as the inner rim. Whites of the eye are grey. Overall, very highly saturated
5. Philip6653: Kinda dark and grey. Nothing jumps out as overly wrong - just a little lacklustre
6. Cassidy: The colours didnt take to the iris very well and the flecks of blue dont blend well with the luminosity. Whites of the eyes look good, just a little too much voer with the pink in the left corner
7. Lorraine: Nice work on the iris, the skintone is a little flat, but by no means the worst. The only thing that really bugs me about this one is the whites of the eyes are a muddle of pink and blue and dont match up with the greyscale.
8. Cupcake: Clearly more than just a recolour. Too much blurring and soft focus. The edges around the iris are too sharp. Whites are a touch too blue but other than that the colouring is mostly good. Shame about the other alterations.
9.irshgrlkc: Oversharpened. Iris - radial gradient? Too perfect to be natural. Veins look like they were drawn on in crayon. Skintone is good but harmed by the over sharpening.
10. Godmother: I hope that was supposed to be eyeshadow. More blurry soft focus. And why the twinkle? The lower lid is a little splotchy and the corner of her eye is purple. Has potential to have been a good entry, if you stuck to just the colour.... though I would like to buy that eyeshadow.
11. Chillin: Skintone is a little too varied, with too much blue in places. Iris has good variation, but looks a little yellow to me
12. Limey-g: Very flat all over and you went over the lines a little. But theres clear attempt to vary the iris colour. Not a bad attempt for a first try.
13. Nanls: Very good colourisation but a little dead. Something I just cant put my finger on. Did you sharpen it or alter the brightness/contrast?
14. Lilsp: Nice iris, maybe a little too soft and blended on the colour variation. Skin is a little pink in places and a dirty yellow in others
15. Karin-l: Skintone - love it. Maybe too pale for some people's tastes but I think its beautiful - very delicate. Veins could have used some work and there could have been some more variation in the iris. Theres also a little bit of colour bleed on the bottom left of the iris but thats just nitpicking. Its a superb piece.
16. Philbach: Very flat colours all over, with a few non-comittal pink viens coloured in. Colour erased from highlight - not sure why.
17. Printmeister: very nice skin colouration, the inner rim is a little orange though, Whites of the eyes also are a little grey/blue. Nice iris colour and reflections.
18. Makeovermagic: Very dark iris and very strong solid edge. But the fleshy parts of the eye are a good colour. Mostly a good effort, but overshadowed by the inky iris.
19. Mike_Warren: Dont take this the wrong way but I think you may need to calibrate your monitor. The eyebrows are green there are purple/blue patches on the skin, mostly under the eye. The colours on the iris are too saturated and dont blend well
20. PhotoB: Another candidate for a slight monitor recalibration. The upper lid is purple. Would like to see some more variation in the iris.
21. woodenbender: Good attempt at skin colour variation - a little mucky green in the shadows. Iris colour is a little too saturated but the colour choices are good.
22. Soleah: The iris colouration is lovely. The whites are a little too yellow - maybe thats what I see when I look in the mirror in the morning but its not what I expect to see in a photograph - if you know what I mean

Skin is a bit pink in places
23. and to prove I'm not a bitch - this is what I tihnk about mine

NancyJ: Nice soft skintone variations, very delicate and pretty. Iris could use a little more colour variation and a little more comittment to which colours. The inner lid could do with being a little more pink. Evidence of pinking to the veins but could be stronger without looking 'crayola'.
24. Chelm: Another murky one. The colours look ok, but just too dark. The whites are a little too blue and the inner rim should be a little pinker than the rest of the skin.
25. Lonk: Very grainy sharpening. A little murky like some of the others, but the skintone is good. The iris colours dont blend very well and dont match the luminosity imo. Very delicate vein work.
26. Marthig: Flat colours. In fact I can only really see 2 colours in the whole picture, the green iris and very pink skin. Harsh edge on the iris. Maybe a few yellow flecks in the center
I cant believe this post isnt too long yet. Well I hope that no-one gets upset but I wanted to be fair and given everyone an honest critique - missing out anyone would be worse than anything I could say - IMO.