Step 1: Assume the centre and radius of the circle.
Let the centre of the circle be \((h,k)\) and radius be \(r\).
Since the circle passes through \((2,3)\), we have
\[
r^2=(h-2)^2+(k-3)^2
\]
Step 2: Use the intercept on \(x=2\).
The line \(x=2\) is a vertical line.
The length of the chord made by the circle on \(x=2\) is \(3\).
The distance of the centre \((h,k)\) from \(x=2\) is
\[
|h-2|
\]
So, chord length is
\[
2\sqrt{r^2-(h-2)^2}=3
\]
Using \(r^2=(h-2)^2+(k-3)^2\), we get
\[
2\sqrt{(k-3)^2}=3
\]
\[
2|k-3|=3
\]
\[
|k-3|=\frac{3}{2}
\]
Step 3: Use the intercept on \(y=3\).
The line \(y=3\) is a horizontal line.
The length of the chord made by the circle on \(y=3\) is \(4\).
The distance of the centre \((h,k)\) from \(y=3\) is
\[
|k-3|
\]
So, chord length is
\[
2\sqrt{r^2-(k-3)^2}=4
\]
Using \(r^2=(h-2)^2+(k-3)^2\), we get
\[
2\sqrt{(h-2)^2}=4
\]
\[
2|h-2|=4
\]
\[
|h-2|=2
\]
Step 4: Find the centre in the first quadrant.
Since the centre is in the first quadrant, we take
\[
h=2+2=4
\]
and
\[
k=3+\frac{3}{2}=\frac{9}{2}
\]
Thus, the centre is
\[
\left(4,\frac{9}{2}\right)
\]
Step 5: Find the radius.
\[
r^2=(h-2)^2+(k-3)^2
\]
\[
r^2=(4-2)^2+\left(\frac{9}{2}-3\right)^2
\]
\[
r^2=2^2+\left(\frac{3}{2}\right)^2
\]
\[
r^2=4+\frac{9}{4}
\]
\[
r^2=\frac{25}{4}
\]
Step 6: Write the equation of the circle.
The equation of the circle is
\[
(x-4)^2+\left(y-\frac{9}{2}\right)^2=\frac{25}{4}
\]
Expanding,
\[
x^2-8x+16+y^2-9y+\frac{81}{4}=\frac{25}{4}
\]
\[
x^2+y^2-8x-9y+16+\frac{81}{4}-\frac{25}{4}=0
\]
\[
x^2+y^2-8x-9y+16+\frac{56}{4}=0
\]
\[
x^2+y^2-8x-9y+30=0
\]
Step 7: Final conclusion.
Hence, the required equation of the circle is
\[
\boxed{x^2+y^2-8x-9y+30=0}
\]