I'm a sucker for ben and jerrys, phish food/ cookie dough.
If it's proper icecream, rum and raisin, there used to be a van in savernak forest which did the best rum and raisin i've ever had, HUGE raisins which just exploded with flavour, strong, sweet rum flavour in icecream. In a waffle cone. Amazing, makes my mouth water thinking about it.
Failing that, anything which is chocolatey will do nicely.
I've also got a strange thing for really cheap icecream on occasion, that really watery overly sweet vanilla tescon value ****, think it's probably because it reminds me of my nans on my dads side lol