Imrans's ODI overall batting average is 33.41, Kapil's is 23.79 - a difference of about 10. In the No.7 position it is 28.52 versus 24.17. Kapil Dev's SR is much higher (95.07 versus 72.65) but this can be explained by the fact that Imran batted more often at No.5 and No.6 where there was less reason to slog. On-the-other-hand the majority of Kapil Dev's innings were at either No.7 or No.8, so he had little choice but to try and hit boundaries. Imran could be just as devastating when he had be, but batting in the middle-order meant that he had to pace himself more.
So all in all, I don't think that we can claim that either batsman is significantly better than the other by looking at ODI stats only.
However, we can say with some certainty that Imran Khan is an intrinically better and more talented batsman than Kapil Dev if we view both ODI and Test match stats combined. Imran's Test average stayed in the mid-30s throughout his career, and finished at 37.69. In the No.6 position for Pakistan he averaged a whopping 61.86 over 20 innings. None of Kapil Dev's figures come close to this number.
If the tail of our selected team didn't consist of Akram-Garner-Murali-McGrath then I may be inclined to pick Dev. However, since I know that Imran's batting technique is more rounded than Dev then I prefer Imran in the context of the team chosen.
In short, Imran's excellent batting technique allows him to play any role required by the situation. He has the better natural ability to play a supportive role and rotate the strike to Viv Richards if that is what he has to do. But also the ability to carve 4s and 6s in the last couple of overs if need be. I see him as more versatile than Dev. At least that's my opinion.
Imran Khan Huge Six v Australia 1992 WC - YouTube
