Question :
I bought an 8GB SD Card the other day, but, it didnt work on my galaxy mini. The guy at the shop said that Samsung Galaxy Mini GT-S5570 can not handle it. So, I am stuck on my 2gb SD Card.
I just wanted to ask you if partitioning this 2GB SD Card, will I be able to make the partition to 500MB ?
The original 180MB for apps is way too low, and I think I could do with 500MB somehow.
Reply :

The guy at the shop probably didn't know much about it. In fact, Galaxy Mini can support sdcard upto 32 GB, however I don't recommend using it, since your device will load slow as it'll take much time to scan the card and load files. 8 GB or 16 GB memory card should be enough for galaxy mini users. Now, for you case, if you are really not satisfied then, I suggest you pay a visit to some other shops and seek for a 4, 8 or 16 GB card. Don't forget to try it out on the spot. It should work fine.
Note : Some cards need to be formatted before you can see or use them.

Also, yes, you can partition your 2 GB card to create a sd-ext partition of 500 MB which should be enough if you are a normal users. Simply follow the step by step instructions given at this article to partition your sd-card. In case you buy a new card, don't allocate more than 2 GB for your sd-ext partition. 500 MB or 1 GB should be enough for normal users.

Also, it is to be noted that, even if you use sd-ext partition (to preserve your internal memory), it doesn't necessarily mean all apps should be installed in sd-ext/app/ directory. Some apps, which support Androids' app2sd (a new feature introduced by Google with Android 2.2.1 Froyo release, which let's developer to install some or all part of application and data to be stored in sd-card.)  feature will be installed in sd-card as usual. This means, most games will be installed in sd-card which justifies the reason why you shouldn't allot more than 1 GB of memory for your second partition in sd-card.

Good luck and happy partitioning.