"silver surfer,doomsday, and spawn and hellboy are tied"
You think they're all tied? Hellboy shouldn't even be on this list and he's nowhere near being tied with any of the others.
"I thought the Surfer could use cosmic power to extend his strength to whatever limit he wanted. I think that makes him the winner."
Theoretically Surfer could increase his power to levels beyond Doomsday's but you would have to lean towards Doomsday, without seeing Surfer ever truly display that level of strength. I havent seen all of Doomsday's appearances so I havent seen a bunch of strength feats from him either, but I'll take him at face value until I have a chance to look into those other showings.