You don't need a new camera, just a new housing that corrects the blur problem.
Granted I did not look into a new housing and maybe should. I was just thinking if I was spending $170.00 for a new housing then 40 dollars on filters plus shipping I am into it for the 250 range. For 150ish more I can get the new tec in the Hero 4. If I was able to get the dive housing for less, I would definitely consider this route as well.
Do you know what firmware is installed on your hero 2?
Not sure however it would likely be the original firmware as I did not even know you could update it!! I'll look into updating it though.
Also, what features are you using (i.e. protune, resolution, etc.)
Not sure what you mean by Protune but the resolution I am currently on is the 1080 30 FPS as that is the only setting I can find. I tried 720 at 60 but the video was very grainy. I also tried WVGA 60 and wide angle. So far the best setting seems to be the 1080 30 FPS on either wide or normal view.
Finally, what SD card are you using?
My SD card is a Patriot LX series 32 Class 10 SD/HC
These are all issues which can cause the performance issues you mentioned. (Your PC and/or viewing program could be the problem too.)
As for viewing, I am using and have always used VLC. Granted I just switched from a PC (core i5) to a mid 2009 MacBook Pro with 8 Gb of Ram and a 1TB Samsung SSD. In hindsight, the performance issues may have been attributed to the fact I was trying to view the footage directly from the SD card as apposed to moving to the first. Unfortunately, I trashed the footage in frustration and can't access it now.
What editing software do you guys generally use? I've never used anything and so far plan on just using iMovie unless there is something else better.