You will possibly find SATA is not supported by your board - it is a little squarish connector. Many new discs (and this is quite popular with retail replacement discs) come with a little utility designed to simply clone your old drive to a the new one and then boot off the new one. In other words replacing a HDD can be very easy.

Provided it can be read at all, of course. In your case, there may be greater or lesser parts of the OS unable to read.

It is not so easy to change the drive type i.e. from IDE to SATA, because this really does not have the correct drivers in your existing copy of Windows. Hence a reinstall is always required in that case, although it can be a 're-install in place' if you have the right CD.

In your position, my recommendation would be a re-install to a SATA drive (if supported - hopefully you have a full install CD, or can borrow one). Having got the new drive working, you could temporarily mount your old HDD in place of the CD/DVD and thus recover any or all data you want to keep.