I'm happy to be posting here on this side of the forum!
I have some questions, please, no spoilers at all. At all. I've had no spoilers since 11/11, I can wait longer still. I was going to search, but there are 3000+ pages on this side of the forum, so yeah.

I am playing a big, burly heavy armor, wearing Nord with a greatsword. I like rending. Just a little restoration, conjuration and alteration. Mostly rending.

Cooking. I'm enjoying cooking. I assume this is for RP only? Can I find and use cooking pots whereever?

How in the world do I pick something up?

All created potions are .5 pounds, even if the ingredients weigh less than that?

Do plants grow back?

Does everything respawn? Inside as well? How long does it take?

Glowing ash piles are cool. Is this gonna be a lag problem later? (Reminded of FO3 lag when I was an energy guy)

Lydia. I love how annoyed she is to carry my burdens. She wears some better things I give her, but not all. She keeps wanting to use a hammer, is that good? What are her skills?

I just bought Breezehome. Can't afford any furniture. Put all my crap in that one chest upstairs. Safe? Will there be more storage when I can afford it? Digging through one chest, makes me cry.

So far I'm having a blast. There are good and bad things, in comparison to Oblivion, where my characters still live, but I'm enjoying my visit.

Hello there, lemme answer your questions once at a time

1. Cooking is for RP only but there are cooking pots in most homes and camps throughout the world of skyrim which you can use.

2. If you mean picking something up as in moving it without taking it then you hold down the X button (for ps3) so whichever button you use for taking something for your inventory, instead hold that button and release when you are happy with where you have placed it.

3. All potions are exactly 0.5Kg despite their ingredients.

4. Plants grow back in the cell (area of the world) in between 25-30 days. However if you re-enter the cell before then, then the plants may reset and it may take them another 30 days to respawn.

5. Most things respawn in the game, it just takes 30 days, but if you enter that area then it may reset. (Hopefully someone can give you a more precise answer here)

6. Ash piles have been around for a while and for some people they stay in their games causing save file bloat and lag, However this is going to be fixed according to the 1.9 patch when it releases.

7.Lydia's skills are primarily one handed and heavy armour, so you may wish to sell the hammer and replace it with a one handed weapon.

8. Yes the more upgrades you get the more storage space you get too. I hope you have a good time with this game as its awesome!

If you have any further questions then just let me know, i will keep my eye on this thread

Yes and no! Not all cooking pots are usable (annoying but true). But you can use all crafting furniture no matter who it belongs to.