I'm sort of a noob when it comes to Fallout. I started with Fallout 3 (for better or for worse) and I loved it. I know I'm going to get flak for saying that but bear with me please. Anyways my question is this, I'm getting very far into the game and it's becoming increasingly difficult to keep Tyco, Ian and Dogmeat alive. If they die does that affect anything? Is it worth keeping them alive at all?

just depends if you want a group or not. It's all personal preference.

I might mix 1 and 2 up, but you should be able to have them wait somewhere while you do the fighting.
Nevertheless it can be convenient to have them draw some fire or take out a bad guy.
Dogmeat kept amazing me with the relative ease with which he can take out an enemy.
Nevertheless he's rather vulnerable to heavy weapons and rapid firing enemies.

@HertogJan
How can I make them wait somewhere?

Just say that they can leave now, and they will wait there.
For Dogmeat, lock it in some room.

Talk to them, tell them you don't want them in the party anymore. With the exception of Dogmeat, they will respond to this statement by remaining in the exact spot where they were standing when you talked to them forever.
That said, the party members of Fallout 1 are more or less superfluous by the end of the game. Canonically, they're all supposed to die anyway, according to the Vault Dweller's diary from fallout 2. Keeping them alive doesn't have any apparent benefits aside from their value as meat shields.
The party members of Fallout 2 are smarter and tougher, and you can give them better armor and weapons to bear. However, they're still not particularly important to the story, so their deaths are not a big cause for grief. The most important parts of the game are won with minimal fighting anyway, so it's not vital that they be there by your side in a fight. This is especially true for Marcus, who I recall killed me and my fellow party members far more often than the enemy ever did... If you add him to your party, make sure he has a rocket launcher and plenty of rockets. Don't give him a minigun of any kind unless you're absolutely sure it's safe.

As others have stated they are pretty much useless other then as meatshields. Once you have the Hardened Power Armor and Turbo Plasma they just pretty much get in the way and little else.

Well that's good to know. Actually I was using Ian and Tyco to hold my extra stuff, so if one of them died it would really hurt me, in a way. I believe I can just pick a random locker and throw everything in there and they should be there forever right?
I also just realized I didn't spell the word "party" correctly. >_<

I never use the NPCs. They just get in your way, and die, usually fairly soon after you get them.

They're quite useful as mules for a while.
After a while they get annoying.
I remember leaving them behind somewhere in both Fallout 1 and 2 when I was ready to face the end boss.

I'm playing Fallout 1 right now, and my concern was whether a bigger party would take away from my XP (sharing XP like in D&D). Thankfully, they don't.
Is it the same in FO2 & 3?

That's affirmative. In Fallout 2, your allies do not detract from your share of the XP. Whenever you level up, there's a chance that they will do so as well. I don't know how Fallout 3's henchman-leveling system works, but I don't believe you lose XP for having a companion in that game either.
One of the perks of a good charisma score, eh?

I beat Fallout 1 without NPCs. You can do the same with the right character and equipment, like in most RPGs. Just remember to use your brain to keep it from splattering all over the wasteland ground.

Party members can be useful if you give them the right weapons. Ian does wonders with the .223 Pistol, Tycho isn't too bad with a good shotgun, and Dogmeat is simply man's best friend. Sure they might not be useful later but Ian always helps me in the beginning. You want to avoid giving them burst weapons; Ian is notorious for hitting you as much as the enemies with an SMG in the hands.
Other than being pack mules and helping you in combat, NPC's in Fallout have no impact on the dialogs and story. Some of them do have some minor effect in Fallout 2 but nothing really major. For exemple you can have Vic meet his daughter in Vault City and later convince her to forgive him for some XP.