Efficient Chunk Loading.

Newbie & Debugging Questions
#1

Lets say I want to load a Map that is 20x20 chunks, each chunk is 10x10x2 blocks, that is a lot of blocks (80,000). So, in a small map, I would just initiate all of the chunks before the game starts, but now, I am interested in more efficient ways. I have tried to only initiate the chunks within a 2x2 area of the player, but RAM keeps stacking (from ~52mb to ~250mb) by the time I trek the whole map. Here is some code I have tried to implement. If anyone can give me a better suggestion, please do so.

private void setView() {
        int lowX = (getChunk((int) position.x, (int) position.z)[0]) - 2;
        int highX = (getChunk((int) position.x, (int) position.z)[0]) + 2;

        int lowY = (getChunk((int) position.x, (int) position.z)[1]) - 2;
        int highY = (getChunk((int) position.x, (int) position.z)[1]) + 2;

        if (lowX < 0) {
            lowX = 0;
        }

        if (highX > width) {
            highX = width;
        }

        if (lowY < 0) {
            lowY = 0;
        }

        if (highY > height) {
            highY = height;
        }

        if (view[0] != lowX || view[1] != highX || view[2] != lowY || view[3] != highY) {
            view[0] = lowX;
            view[1] = highX;
            view[2] = lowY;
            view[3] = highY;
            loadChunks();
        }
    }

    private void loadChunks() {
        for (int x = 0; x < width; x++) {
            for (int y = 0; y < height; y++) {
                if (x >= view[0] && x <= view[1] && y >= view[2] && y <= view[3]) {
                    chunk[x][y] = new Chunk(x, y);
                    chunk[x][y].setTexAmount(4);
                } else {
                    chunk[x][y] = null;
                }
            }
        }
    }

private void renderChunks() {
        int lowX = view[0];
        int highX = view[1];

        int lowY = view[2];
        int highY = view[3];

        for (int x = lowX; x < highX; x++) {
            for (int y = lowY; y < highY; y++) {
                chunk[x][y].renderChunk();
            }
        }
    }

If it matters, I am using Vertex Buffer Objects for all of my 3D rendering.

Also, a sub question: Would it be worth the code for me to convert my 2D HUD from immediate mode to VBO?