Hi,
Some 'point & shoot' cameras can give you some/all control over iso/aperture/speed (this is what the presets generally do for you) It does depend on camera, grey answer I know...sorry.
The best advice is get familiar with your camera. From this you will know what it can/can't do & its limitations - it is really the only way.
Easiest way is to set a subject, eg still life is good (it doesn't move or get impatient!) & play with the various settings whilst taking pics of the same subject then look at them on PC (view the exif data (if you can) to see which set of conditions look the best.
Unfortunately, there is no quick way - just practice & ask for advice (a thick skin can be useful - if you are easily offended )
HTH
Mark
PS. FYI I have now migrated from a Canon IXUS compact to Nikon D40 then to Nikon D200 & Nikon D700
As said some P and S and all Non DSLR " Bridge" do but in P and S these ar mainly menu based and not easy to adjust on the fly
Also even with some of the Non DSLRs the adjustable ranges are narrow and effects dont seen obvious
As such it seem to be that if you want to learn these settings and a DSLR would offer the widest scope
I'm actually looking for a new P&S compact after my last one packed up - currently eyeing a Sony DSC W550 (£129 from Comet - I've got some vouchers). I's love to go DSLR but the cost is a little scary when I'm not convinced I'll be able to take better pics than I can with a compact.
I actually tried using the 2/3rds rule last night with my phone and it's suprising how much improvement there was in pics of my untidy living room! I always thought the "grid" was something to do with autofocus for some reason...