At first we thought the effects might have been a casualty of the process of cramming three games onto one disc, but this video shows that the Japanese version of Prime on Wii, which had a Wii disc all to itself, also lacks the freezing effect (skip to the last thirty seconds to see). So what happened? It could merely be a glitch, or the result of a hasty port. It's certainly nothing to get too upset or burn your Trilogy disc over. Just kind of ... odd.