I thought I would report this so it would be able to be found by others with the problem (because it's so weird).
I have 2 laptops, one is an Acer 5100 (currently using a wired connection) and an Acer 5050 (using wireless). Both update once a week and are always updated.
After upgrading both to 10.04 (clean installs), both would randomly freeze as evidenced by the screen going to a random blocky pattern and/or lines. They would go from 6 hours to 2 days, before doing it. The 5100 is on my desktop (just plays music mostly), and the other is on once in awhile at night in the living room (it's never happened when I am out with it).
So, one day after about a month of this, I see that the 5100 is on and normal and I go to nuke a cup of coffee and when it is done I go back to my office and it has frozen again. Hmm, I say. Never correlated it. Since I don't use the wireless on that machine I hit the slider to shut it off.
It's been about 1.5 months and it's been fine ever since. The 5150 still does it randomly since I use the wireless connection for it.
Microwaves and wireless work in the ballpark of the same frequencies.
Now if someone has any other explanations, I am open to suggestions, but it seems pretty cut and dried to me.
Or, I am completely out to lunch, in which case feel free to laugh!