I find that until you can get a lot of solar/wind/water or nuclear that industrial craft is super fuel inefficient when compared to thermal expansion and railcraft steam. Using forestry's automatic peat bog will go a long way in saving precious coal. (Using coal as a fuel is almost always a waste nowadays - use it for coal coke steel and coal dust). If you're baffled with what to do with your vast quantities of silver and lead - use it to set up factorization power for a solar furnace heater powering a slag furnace.
That said, IndustrialCraft gives awesome toys like jetpacks and mining lasers. Thermal Expansion and Railcraft are my favorites for infrastructure and ore processing (minecarts and loaders are comparable to redpower tubes in terms of precision sorting and automation). As for toys to start with, your first 4 obsidian should be spent making a pair of portalgun's long fall boots.
Well Geothermals work pretty well, exspecially with TE. Thanks to TE the Solar-Nerf in Gregs isn't a problem, since a Magma-Crucible supplied with enough Netherrack easily powers your Magma-Engines and Geothermals and you can even output from a Crucible directly into the Geothermal. Technically you could even save the Magma-Engine and only use Geothermals and Electric-Engines (Lava-Cells give you 50.000 EU in a Generator, but only 20.000 in a Geothermal, so 1000mB Lava pumped in should do the same, which are 8.000 MJ via the Electric-Engine + Iron-Tube), although this is not as effectiv, you only need 4.000 MJ to turn Netherrack into Lava
*Note, Although NEI tells you that a Bucket of Lava only gives 5.000 EU it will give 20.000 EU
And yes saving coal is important in FTB. If you need some fuel early use charcoal, which is easy to produce in large amounts (with a tree-farm from forestry or manual wood-chopping with a chainsaw, it might still be an important factor later on).
But Lava is your Number 1 Fuel for most of the game. So what you want to do very soon is getting some important items:
1. A Bucket to build a Portal
2. Lava
3. A Compressor
You need the portal to get Netherrack, you need Lava to build the portal and you need the compressor to turn netherrack into netherbrick for the magma-crucible. Since you need a Generator anyway to power the compressor build a Geothermal.
So my suggestion is very basic:
1. Start with Geothermal, Electric-Engine and Magma-Crucible, since you won't run out of Netherrack and the loss of efficiency is toleratable at this point, but since EU-Storage is very simple and you can easily hook up the system with a Generator that you feed off charcoal it works pretty well.
2. As soon as you have enough stuff to build a Storage-Cell (the correct name would be Redstone Energy Cell) you can seperate your EU and MJ-Production and use more effective Magma-Engines, since you are now able to store MJ as well as EU.
3. The EU-Values of some items are a bit strange. If an Item has a EU-Value this value means what it is worth inside a Generator, the Heat-Value describes its effect in a Geothermal. So a Lava-Cell produces 50.000 EU inside a Generator and only 20.000 inside a Geothermal (and 1k Heat in a Railcraft-Steamboiler). A Bucket of Lava produces 5.000 EU inside a Generator (although this does not seem to work as I tested it, the Generator is not accepting Lava-Buckets), 20.000 EU in a Geothermal (since it is also 1.000mB Lava) and also 1k Heat for Railcraft-Boilers. I'm not sure what the extra 2k-Heat for IC2 means.
If the Generator would work with Lava-Capsules as a replacement for Lava-Cells IC2 would beat TE for efficiency, since this would mean that 1000mB Lava is worth 20.000 MJ instead of 18.000 with the Magma-Engine if not used permanently. Also with the recent nerf to Lava for Boilers you can not build a selfsustaining Steam-Boiler like you could before (since FTB A is still 1.4.2 you won't notice this).
If anything in IC2 doesn't match the Wiki (or for any other mod) it is most likely Gregtech messing with the recipes, just go with it. It makes the mods more challenging but it also adds a lot of things I enjoy like the rockcutter.
If you are new the recipe-changes don't hurt that much, since you are not used to the original ones. And like always, if you have questions, which can exspecially arise if you work with certain machines, just ask. If you do it in a friendly way you will most likely get even the most stupid question answered.