I've played this game over and over throughout the years and LOVE it. The only problem is that I keep running out of money long before I train as much as I have exp for. I read somewhere about dropping money into the band and then doing the week of work thing for 100 years or so.
My questions are:
-What is the effect of aging?
-Can I actually die from old age?
-If some of my party dies from old age can I just recruit other, younger, characters and keep the money I have in the bank?
-Has anyone ever done this and can advise on the best way to go about it?
Thanks!

Excessive age will begin to add a penalty to some stats, eventually characters will die of "old age" (actually they die because their endurance (and therefore their HP) reaches 0, so they can't be resurrected because they have no HP), and yes, you can replace them as they get old.
Best way to do it is to complete Vertigo, clearing out all the slimes and bugs, level up a couple times, then tell the mirror "Rivercity" to go straight there. If you don't clear Vertigo and level up, you might have some difficulty with the beggars. Once in Rivercity, go to the work place, work for a year, back to the bank, put it in, repeat. Eventually the interest is higher than the money you're making so putting it in the bank isn't as important as just wasting time really fast.
DO NOT GO ABOVE 4 billion! You can have 4 billion(ish) gold in the bank, and another 4 billion in hand. If you add more, it will wrap around to 0 and all that time will be wasted. I suggest stopping at about 3 billion in both hand and bank.
Once you've got your 6 billion combined or your characters are 60 years old, just go to the inn and replace them. They all start at level 1, so buy some good weapons and then tell the mirror "Warzone" so you can fight a few low level monsters to replace the ones you defeated with the first group. Should add a few days, but you need the extra experience.
And then you'll never be wanting for money again, and no other ill effects will happen. The story proceeds as normal and no one else has aged, even though it's now 50 or 60 years later.
There are bits of unused code that I've come across which suggest that there was supposed to be a time limit, but it's incomplete so the idea was probably scrapped.

You could teleport to Shangri-La, buy Lloyd's beacon there and use the spell to get back to Vertigo. Afterwards rest and say "count du money" to the mirror. Collect the treasure heaps and use beacon to get back. Afterwards I'd explore the town (you can get many expensive items but hardly any XP there, you could even use save/reload to enforce finding/stealing valuable stuff), it's your decision if you collect the reward from the major or save the XP gain it for the real party. Sell everything you don't need for fighting to the merchant and put all money to the bank.
When you teleport the well equipped level 1 party to Rivercity you should be able to shoot the insane beggars from the distance to get to the jobs, the robber in the bank can be defeated with a little luck. Now you can work and take your money to the bank as often as you want.
If you replace your characters in Castleview instead of Vertigo the new characters will start at level 5, you can get there without fighting a single monster.

When I needed cash for training at the end of Xeen, here's what I did.
First, make sure you have at least one merchant to handle buying and selling (I train all of my characters as merchants anyway), and put most of your gold in the bank - it earns interest.
1) Teleport to each town and buy up any expensive nonmagical armor (i.e. no prefix or suffix), namely plate mail and plate armor.
2) Use the Enchant Item spell to enchant the armor, then resell it for profit. If you want to speed things up, save your game first, and reload until you get pricy results like obsidian and diamond (this also lets you cut out unfavorable results like wood or leather).
3) Bank your profits from step 2, then visit the taskmaster and work for a week. Afterwards, you'll find that all the shops have restocked and you've earned some interest on your banked gold.
Repeat steps 1-3 as long as you like. Keep as much of your gold in the bank as possible to maximize your earned interest. I was able to rack up enough cash to fully train my characters in just a couple of game years. I haven't tried the other methods posted - I was at the end of the game, after all - but this one worked very well for me.

How do i resurrect?

If a character is just unconscious a simple healing spell will bring them back. If they're dead (RIP picture) then you'll need a Raise Dead spell. If they're eradicated (skeleton picture) then you'll need the Resurrect spell. If your characters can't use the necessary spells then you'll need to pay a visit to a temple and cough up some gold.

yea thanks but got one more question:
Where can i learn those spells? :D

If you're still talking about World of Xeen, clerics and paladins can learn them at wizards' guilds. The first few guilds you visit won't have these advanced spells, though. Early on, it's best just to save often, rather than spending a lot of money at the temple.
Incidentally, make sure to check your characters' equipment when you raise them. There's a good chance that their gear has been broken, especially if they were eradicated.

In Clouds of Xeen Raise Dead and Resurrect can be bought in Asp, Winterkill, and Shangri-La. Various cure spells can be bought in pretty much every town.

I got them now thank you