More RAM? Or external Hard Drive?

I have a 13-inch white Macbook (2.1 GHz Intel Core 2 Duo) with 1 Gb of RAM and 111.5 Gb hard drive.

About half of my hard drive space is devoted to an iMovie project that, quite frankly, has been years in the making and has become more of an epic than I ever intended it to be! The problem is I now find it really difficult to add on any more footage or to edit the footage I have. I have managed to clear about a gig of space on my hard drive by moving most of my files to my old desktop and trashing a lot of stuff I don't use or need. I've also been ruthlessly pruning a lot of the clips stored in the iMovie Events library although sometimes I get a message saying I don't have enough hard drive space to move the clips to the trash! And sometimes I end up losing footage I hadn't selected for the trash, which I can only assume is a glitch in iMovie.

My question is this : I'm going to finish this movie if it kills me, so what do I need to do to make my laptop run better? Do I need more RAM, or do I need to buy an external hard drive? Originally, I figured that it was probably a RAM issue and a guy at the Apple store agreed with me. But, now I'm not so sure because a) what do I know? and b) maybe I didn't explain the problem clearly (and maybe I'm still not!) Either option is fine by me but I want to be sure I'm making the right decision.

Can anyone help?

Has to be a Ext HD i think. Especially if you are getting msg saying you dont have the room. They are cheap enough now able to pick up a 500GB for $60 or there abouts. The 2nd thing you will get with a Ext drive is a BackUp.
If this movie has been 2 yrs in the making then i would be trying to protect that data any way i can. RAM can come later BUT YOU NEED A EXT for BackUp . . . .

I agree with the above, but you'll also want to check that you are not paging all the time, because that will slow you down hugely. 1 gig of ram is pretty tight for any kind of video, and ram is pretty cheap these days - honestly I would do both.

What is your budget? I would recommend the same - go get ram and external drive if you have the funds.
If this is your MacBook - it looks like you can go to 6gb.
MacBook "Core 2 Duo" 2.1 13" (White-08) Specs (Early 2008, MB402LL/A*, MacBook4,1, A1181, 2242) @ EveryMac.com
Or you can use owc to figure out what will fit.
Apple MacBook Model Selector Guide for Memory (Ram) and Hard Drive Upgrade options
But editing video really can benefit from more ram and more hard drives.

Also what are you using for editing? Adobe suggests 3 drives for Premiere. I have a 17" so I have 1 ssd in the pci express for video cache, a FireWire 800 drive for audio cache, and my main drive is where the application lives.

And did you see the movie"How to Succeed in business etc" ? Great line there says "Hard work never killed anyone" as he falls off the perch. Your HDD is a bare minimum and 1GB memory is zilch compared to the tasks you are carrying out.

As a suggestion a new internal SSD, and the 111GB into a Firewire external case, erased, and used for the movie.

So, the answer is : Get both? I should have known!
Actually, that's OK. That's manageable.

IvanLasston - I'm not using anything fancy. Just the iMovie09 package. It's a hobby really, but I'm determined to get it finished. It's my fault for being too ambitious.

Oh, and TatooedMac? Make that more than 10 years in the making! I started with some stuff I shot on video in 1997 and I've been adding to it with a miniDV camera for the last 3 or 4 years.