Is my plan a good idea?

[Saint]

So, I have a bad CPU and GPU, however I like cracking hashes. My plan may work, or it may not, please help me.

Plan:

1. Buy a 1TB external hard drive.
2. Download a crap load of wordlists.
3. Sort them if I can be bothered
Now since my hardware is bad I thought this would make thing a little quicker.
4. Make a rainbow table out of those wordlists, so my hardware dosn't have to hash the word every time I run them.

But I am knew to lookup/rainbow tables. If I had 100GB of wordlists, how big would the tables be in size? Also, if it took me 2 hours to run through 100GB of lists, how long would it take on to run through the table?

I am aware that I can only make the table in one algo.

Profit, or not?

Thanks for your help.