I know this chart is mainly geared toward gaming but it groups CPUs and tries to point out what would be logical upgrades based on performance. I think it's likely to apply to your multi-media tasks as well.
THG recommends moving up three tiers higherGaming CPU Hierarchy Chart
3 tiers above your E5200:
Core 2 Quad Q6700, Q9300, Q8400, Q6600, Q8300
Core 2 Duo E8600, E8500, E8400, E7600