Antmf,
I'm pleased that you're enjoying Civ.
'Noob' Guide
If you've yet to see it;
Sisiutil's Strategy Guide for Beginners contains a ton of handy tips for players up to Noble level (albeit most of it is still relevant at more advanced levels than Noble).
Over-Expansion
The issue of over-expansion and commercial pain is one of the thorniest problems for players - and one deliberately designed for Civ4. Earlier versions of the game allowed for REXing (rapid expansion) - simply a land-grab for cities by churning out Settlers as quickly as practicable. Commercial pressure plus some increased Barbarian activity has curtailed the effectiveness of REXing for Civ4.
The commercial predicament can be dealt with in many ways - razing enemy cities and pillaging enemy lands, cottage spamming in your food-rich cities, leveraging Wonders with commercial benefit such as The Great Lighthouse, The Temple of Artemis, The Colossus, etc., are just some of the tactics for addressing this in the early game. Perhaps the best recognised one is to acquire
Currency (
include
in trades, adds a free
to all cities, can build Market > Specialist Merchants, Wealth) and
Code of Laws (
Courthouses, Forbidden Palace, The Caste System > Specialist Merchants) as priority technologies.
'Good leaders' for new players
The Roman empire presents itself as a tribe that is good to play if you're struggling at a new level, because if nothing else, the Praetorian unit is so powerful, and it will allow you to expand, take over at least one neighbour, and possibly beat another down to a minor tribe at best. Over-expansion is a big trap for this tribe, but if you're prepared to raze enemy cities rather than keep them all, you can work your way towards Code of Laws for cheap Courthouses. Treat the Praetorian though as 'riding a bicycle with training wheels' - it's a crutch that you can use to get you ahead, but throw it away once you're starting to feel a sense of confidence on a level.
I would otherwise suggest Spiritual leaders largely for the 'No Anarchy' bonus. The decision to swap and test out different civics without the anarchy penalty will allow new players to try different civics out with minimal cost.
As time goes by, and you're feeling 'comfortable' but not 'too confident', you should be able to go with random leaders or start experimenting with other traits.
Enjoy!
