Upgrade a mid 2010 Mac Mini or buy a new one?

I have a mid 2010 Mac Mini with a 2.4 GHz Intel Core 2 Duo processor, 2 GB SDRAM DDR3, and a 320 GB HDD. I use it primarily as a way to watch movies, TV, and internet videos on my TV. However, lately it has become excruciatingly slow with choppy video playback. I realize upgrading the RAM and/or the HDD to a SSD would offer an improvement. But my question is, would it be better to upgrade a computer that's getting close to 5 years old now, or buy a new Mac Mini, despite the complaints I've heard about the inability to upgrade RAM and/or hard drive.

Thanks