Rendering and saving video for the long term

I've got two years worth of video folders piling up that I have finally decided to edit. I just purchased Sony Movie Studio 12.

The majority of my videos were taken with my Panasonic HDC-TM700 which creates its video files with the following characteristics :

Type of file : AVCHD Video (.m2ts)
1920x1080
Data Rate : 24438 kbps
Total Bit Rate : 24694 kbps
Frame Rate : 59 frames/second

I'd like to edit and burn most of my videos to BluRay and have managed to create my first DVD with success. But I am a little unsure of what to render these movies to for long term storage on my hard drive. I have been told by others that you should just buy a large external hard drive and keep all your files in raw original format. I understand that but... I really feel that once I edit these files into various projects, all I am going to want are the final rendered files to view and possibly re-burn in the future. It’s very unlikely I’ll look back on the old raw footage but will want to view my finalized projects and don’t want to rely on having Movie Studio version 13 or 14 in the coming years.

What’s the highest possible quality I can render and save to? What I’ve learned so far is :

1. I know I can create .ISO file images of the BluRay project for re-burning later but I don’t think you can open and view those when sitting at your computer, right?

2. It looks like the best option is “Blu-Ray 1920x1080-24p, 16 Mbps video stream” but I have been told that 16Mbps is quite low and I should be targeting something at 32 Mbps or higher? I don’t see that as an option anywhere Movie Studio.

3. Aren’t my original files 24 Mbps anyways?

4. I’ve read John Rofrano’s comments about rendering video and audio separately because of “DVD compliant streams” and I think I understand that.

Thanks for reading my wall of text. I appreciate all input!

In both suggestions, you advised that I go with 60i options. I am pretty sure that my original footage is non-interlaced, progressive scan. Doesn't 60i imply interlaced?

I tried it and it dropped my bit rate to 16 Mbps when rendered. So what's preferable? 30 fps + 24 Mbps or 60 fps + 16 Mbps ?