How to determine why my site is slow? Server or Database?

I'm a pretty good SEO guy but know close to nothing about programming. I've got a site hosted on a Mediatemple.net grid server running php & SQL lite, drawing from a database of around 7000 home listings and approximately 50,000 small images.
(I'm also a Realtor and in this market it's bad enough if you have a fast loading site, with a slow loading site my visitors are just going elsewhere)

I don't know how much you can tell just from loading a page and looking at the page source but could someone who's a lot smarter than myself take a quick peek at this and shed some insight?

The site is bwbeach dot com

If you need additional info about the host, programming etc let me know and I will do the best I can to provide additional info.

Could this slowosity be solved by switching to MySQL or do I have programming issues?

Thanks in advance. I've been searching the net for answers for hours without much luck.

You can determine it by loading those pages whcih are not linked with the database. If they work fine they its ok and the problem is in your database.

Hi
I am Danial. I heard about a new faster database solution i.e. LEXST. It can help you as it concerns it shows the search results just within 0.1-0.5 seconds. Please research on it and also share your experience with me. Because i also want to use this database. You can find it on lexst.com.
Thanks to you
Danial!

Try NitrosBase, it is the fastest.

Thanks for kind information. I dont know how to compare/measure the speed of the database correctly. would you please tell me how did you compare/measure the speed of NitrosBase to LEXST? Please mention here so I could measure myself and also could chose which one is fastest..

Thanks in advance..

Before jumping to any new database, Can you provide us bit more information like how big is your database ? what kind of server are you using ?

From there may be I can try to walk you through more specific problem you might be seeing