A/C and heat questions

[DRASTiK]

My 84 suburban has front and rear a/c and heat. There are a few different problems I'm having with them:

First: The front a/c is cold, but won't blow hard at all. When it's on low, it makes a loud rattle noise, as if something's caught in the blower, but on high it doesn't make the noise, it just doesn't blow very hard.

Second: The rear a/c also makes this clatter noise as if something's caught up in it, and it only functions on high. it won't even cut on if it's turned to low.

Third: The front heat doesn't work at all. If you push the knob from cold to hot, the temp of the air never gets hot.

If any of you are familiar with any of the above, please chime in and give me your opinions.

Thanks in advance,
Dave